PURCHASE AND ASSUMPTION AGREEMENT

EXHIBIT 2.1

PURCHASE AND ASSUMPTION AGREEMENT

THIS PURCHASE AND ASSUMPTION AGREEMENT (the “ Agreement ”) is entered into as of September 12, 2007, by and among Brooke Savings Bank, a federal savings bank (“ Purchaser ”), Brooke Corporation, a Kansas corporation and a holding company of Purchaser ( “Holding Company” ), and Bank of the West, a California banking corporation (“ Seller ”).

In consideration of the foregoing premises, the mutual promises herein set forth and other valuable consideration, the parties hereby agree as follows:

ARTICLE I. DEFINITIONS AND CONSTRUCTION

1.1 Definitions . In addition to the definitions set forth elsewhere in this Agreement, the following terms have the indicated meanings for the purposes of this Agreement:

(a) “ Account ” means a deposit account relationship with a customer identified by Seller as having been referred to Seller by the Network which account has not been closed by Seller or the customer or transferred to any of Seller’s other operations or branches in accordance with Section 4.5(a) prior to the Closing or, prior to the date hereof, transferred to any of Seller’s other operations or branches in the ordinary course of business or upon the request of a depositor.

(b) “ Accrued Interest ” means as of any date (i) with respect to a Deposit, interest which is accrued on such Deposit to and including such date and not yet posted to the relevant Deposit Account, and (ii) with respect to a Loan, interest which is accrued on such Loan to and including such date and not yet paid.

(c) “ ACH ” shall have the meaning set forth in Section 6.11(a).

(d) “ Affiliate ” means, with respect to any person, any other person directly or indirectly controlling, controlled by or under common control with such person. As used in this definition, the term “person” shall be broadly interpreted to include, without limitation, any corporation, company, partnership and individual or group.

(e) “ Assets ” means all Loans and all Deposit Overdrafts existing on the Closing Date.

(f) “ Assignment and Assumption Agreement ” shall have the meaning set forth in Section 5.1(a)(2).

(g) “ Assumed Deposits ” means all Deposits existing on the Closing Date.

(h) “ Book Value ”, with respect to any Liabilities or any Asset or group of Assets, means the dollar amount reflected on the books and records of Seller as of the Closing Date, after adjustment for differences or offsets in accounts, suspense items, unposted debits and credits, depreciation, and other similar adjustments or corrections all in accordance with generally accepted accounting principles and regulatory accounting principles applicable to Seller.

(i) “ Business Day ” means any day other than a Saturday, a Sunday or a day observed as a bank holiday by the Federal Reserve Bank of Kansas City or the Federal Reserve Bank of San Francisco.

(j) “ Closing ” shall have the meaning set forth in Section 2.2(a).

(k) “ Closing Date ” shall be the first Friday following the date on which all conditions precedent set forth in ARTICLE V have been satisfied (other than those conditions which, by their terms, are to be satisfied at Closing) or waived and the day prior to the Conversion Date, or such other date and time as may be mutually agreed by the parties.

(l) “ Conversion Data ” means the information and data reasonably necessary in order to convert the Assets and the Assumed Deposits from the books and records of Seller to the books and records of Purchaser. Such Conversion Data will include test tapes and conversion tapes but will not include the Records.

(m) “Conversion Date” means the first Saturday following the Closing Date.

(n) “ Damages ” shall have the meaning set forth in Section 9.2.

(o) “ Department ” means the California Department of Financial Institutions.

(p) “ Deposit ” means a deposit liability with respect to an Account, as of the close of business on the Closing Date, which constitutes a “deposit” for purposes of 12 U.S.C. Section 1813(1), including, without limitation, all demand deposits, NOW account deposits, time deposits, savings deposits, money market account deposits, IRA Deposits, checks deposited for collection and all other uncollected items included in the depositors’ balances and credited on the books of Seller and Accrued Interest, but excluding any deposit liabilities which, by law or contract (including the terms of any relevant deposit agreement), either Seller is not permitted to transfer or otherwise dispose of in the Transaction or Purchaser is not permitted to assume. A list of the Deposits and the balances of such Deposits, as of July 31, 2007, is attached hereto as Schedule 1.1(p) . The term “Deposit” shall not include any deposit Account maintained by Seller as trustee of any trust (other than IRA Deposits).

(q) “ Deposit Overdraft ” means, as of any date, overdraft balances in any of the Deposit Accounts.

(r) “Deposit Premium” means an amount calculated by multiplying each category of the Assumed Deposits by the following applicable percentages:

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provided , however , that the Deposit Premium shall not exceed three million three hundred thousand dollars ($3,300,000) or be less than two million seven hundred thousand dollars ($2,700,000).

(s) “FDIC” means the Federal Deposit Insurance Corporation.

(t) “Holding Company” shall have the meaning set forth in recitals hereto.

(u) “ IRA Assumption of Liabilities ” shall have the meaning set forth in Section 5.1(a)(4).

(v) “ IRA Deposits ” shall have the meaning set forth in Section 2.3.

(w) “ IRC ” means the Internal Revenue Code of 1986, as amended.

(x) “ IRS ” shall have the meaning set forth in Section 3.1(j).

(y) “ Liabilities ” means the Assumed Deposits together with Seller’s obligations to provide services from and after the Closing Date under the written agreements which govern the relationships between Seller and the Assumed Deposit and Loan customers.

(z) “ Lien ” means any lien, claim, security interest, charge, encumbrance, option or adverse claim, except for (i)  statutory liens securing payments of taxes or other matters, not yet due, (ii)  obligations relating to Deposits which become subject to escheat in the year the Closing occurs, and (iii)  such imperfections of title as do not materially and adversely affect the Assets or the Liabilities subject thereto or affected thereby.

(aa) “ Loans ” means those loans listed on Schedule 1.1(aa) as of July 31, 2007 and any grant of credit (other than first mortgage loans) under a written agreement entered into by Seller with borrowers referred to Seller through the Network after July 31, 2007, which is not more than sixty (60) calendar days delinquent as of the Closing Date and has not been paid in full at the time of the Closing.

(bb) “ Network ” means those individuals or small businesses in the State of Kansas who have contracted with Seller to act as Seller’s customer representative and liaison in soliciting applications for Seller’s deposit and loan products, assisting in explaining Seller’s products to current or prospective customers, assisting in obtaining and reviewing customer identification information and forwarding such information to Seller, maintaining the relationship between Seller and customers, and otherwise performing related activities as requested or directed by Seller under the terms and conditions of the contractual agreement, and under the direction and supervision of Seller’s management.

(cc) “OTS” means the Office of Thrift Supervision.

(dd) “ Public Fund Deposits ” means deposits of a Kansas governmental unit or agency, which are secured by pledged assets of Seller.

(ee) “ Purchase Price ” shall have the meaning set forth in Section 2.2(b).

(ff) “ Purchaser Closing Documents ” means those documents and other deliverables more fully described in Section 5.1(a).

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(gg) “ Purchaser’s Knowledge ” means actual knowledge without having conducted any independent inquiry or investigation of an employee of Purchaser holding a title of Senior Vice President or above.

(hh) “ Record ” or “ Records ” means all papers, microfiche, microfilm and computer records (including but not limited to, magnetic tape, disk storage and printed copy) that are Seller-generated or maintained by Seller that are owned by Seller and relate to the Assets or the Liabilities, including without limitation, records pertaining to the Assumed Deposits. Purchaser understands and agrees that all Records consist of copies, except notes and deeds of trust relating to Loans, which are in whatever other form or medium then maintained by Seller.

(ii) “ Regulatory Agency ” means the Department, the FDIC or the OTS.

(jj) “ Requisite Governmental Approvals ” has the meaning set forth in Section 4.4.

(kk) “ Seller Closing Documents ” means those documents and other deliverables more fully described in Section 5.2(a).

(ll) “Seller’s Knowledge” means actual knowledge without having conducted any independent inquiry or investigation of an employee of Seller holding a title of Senior Vice President or above.

(mm) “Settlement Account” means that certain deposit account to be established and maintained by Purchaser in accordance with Section 4.9.

(nn) “ Transaction ” means the transactions contemplated by this Agreement.

(oo) “Transfer Instruments” means any conveyance instruments relating to all Assets (other than the Assignment and Assumption Agreement and the IRA Assumption of Liabilities) that Seller or Purchaser reasonably determine to be necessary to consummating the Transaction, all of which shall be in form mutually acceptable to Seller and Purchaser.

ARTICLE II. Purchase, Sale and Assumption

2.1 Assumption of Liabilities and Transfer of Assets . Subject to the representations and warranties of the parties hereto and the terms and conditions herein stated, on the Closing Date (a)  Purchaser shall assume the Liabilities and (b)  Seller shall sell, convey, transfer, assign and deliver to Purchaser, without recourse, and Purchaser shall purchase from Seller, the Assets.

2.2 Closing and Price .

(a) The closing of the purchase and assumption transaction described herein (the “ Closing ”) shall occur in the offices of Bryan Cave LLP in Kansas City, Missouri, at 10:00 a.m. local time on the Closing Date, or at such other place and time mutually agreed upon by the parties hereto, and shall be effective as of 12:01 a.m. local time the following day.

(b) The “ Purchase Price ” shall equal the aggregate amount of the Assumed Deposits, less the Deposit Premium and less the aggregate net Book Value of the Assets (plus Accrued Interest and net of escrow balances). The Purchase Price to be paid on the Closing Date shall be calculated based upon the Seller Closing Document provided pursuant to Section 5.2(a)(3).

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The Purchase Price shall be deposited into the Settlement Account on the Closing Date by Seller. Seller will wire transfer the funds in the Settlement Account to Purchaser on the morning of the first Business Day following the Closing Date. Within 30 days following the Closing Date, Seller shall provide to Purchaser a final listing of the Assets and the Assumed Deposits as of close of business on the Closing Date. Seller shall pay to Purchaser any amount by which the final Purchase Price exceeds the Purchase Price paid on the Closing Date, or Purchaser shall pay to Seller any amount by which the Purchase Price paid on the Closing Date exceeds the final Purchase Price, such payment to be made (as applicable) on demand by an appropriate credit or debit to the Settlement Account.

(c) FDIC deposit insurance assessments relating to the Assumed Deposits shall be prorated between the parties. With respect to the proration of such FDIC deposit insurance assessments, Purchaser shall reimburse Seller on demand for the amount of any deposit insurance assessments that Seller is required to pay for periods in which the Assumed Deposits, net of Deposit Overdrafts, existing on the Closing Date are included in Seller’s deposit insurance assessment base but during which periods Purchaser has liability for the Assumed Deposits.

2.3 IRA Deposits . With respect to Deposits that are individual retirement accounts consisting solely of Deposits, created by a trust for the exclusive benefit of an individual or his or her beneficiaries in accordance with the provisions of Section 408 of the IRC (“ IRA Deposits ”) as to which Seller is the custodian or trustee, Seller will use commercially reasonable efforts and cooperate with Purchaser before and after the Closing Date in taking whatever actions are reasonably necessary to accomplish the appointment of Purchaser as successor custodian of all such IRA Deposits (except self-directed IRA Deposits) pursuant to a form of appointment acceptable to Seller and Purchaser. Effective as of the Closing Date, Purchaser will accept appointment as custodian with respect to such IRA Deposits and will perform all of the duties so transferred and comply with the terms of Seller’s agreement with the depositor of the IRA Deposits affected thereby. The form of Seller’s agreement for IRA Deposits is attached as Exhibit A .

2.4 Public Fund Deposits . With respect to Public Fund Deposits, Seller will make commercially reasonable efforts to obtain the consent of the public entity for the transfer of such Deposits to Purchaser. If such consent is not obtained, such Public Fund Deposits will be excluded from the Assumed Deposits. With respect to Public Fund Deposits for which consent to transfer to Purchaser is obtained prior to Closing, Purchaser will be responsible for entering into any necessary contractual arrangements with the public entity, ensuring that Purchaser is authorized to accept public entity deposits and making necessary arrangements to have collateral available for pledging to adequately secure such Public Fund Deposits. A list of Public Fund Deposits as of July 31, 2007 is attached as Schedule 2.4 .

ARTICLE III. Representations and Warranties

3.1 Representations and Warranties of Seller . Seller represents and warrants to Purchaser, as of the date of this Agreement and as of the Closing Date, that:

(a) Seller is validly existing as a California banking corporation and in good standing under the laws of the State of California. The execution and delivery by Seller of this Agreement and the Seller Closing Documents and the consummation by Seller of its obligations hereunder are within Seller’s power as a California banking corporation, and have been duly authorized by all necessary corporate action on the part of Seller. This Agreement has been duly executed and delivered by Seller and, subject to all Requisite Governmental Approvals, constitutes Seller’s valid and binding obligation, enforceable against Seller in accordance with its terms, except as limited by bankruptcy, receivership, conservatorship, insolvency, reorganization, fraudulent transfer, moratorium and similar laws affecting creditors generally and by the availability of equitable remedies. The Seller Closing Documents and the Transfer Instruments (to the extent required to be

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executed by Seller), when executed and delivered by Seller, subject to obtaining all Requisite Governmental Approvals, will constitute valid and binding obligations of Seller, enforceable in accordance with their respective terms, except as limited by bankruptcy, receivership, conservatorship, insolvency, reorganization, fraudulent transfer, moratorium and similar laws affecting creditors generally and by the availability of equitable remedies.

(b) The execution and delivery by Seller of this Agreement do not, and the consummation by Seller of its obligations hereunder will not, result in (i)  any violation by Seller of (A)  its charter documents or bylaws, or (B)  any order, writ, judgment or decree of any federal or state court or governmental authority or regulatory body having jurisdiction over Seller to which Seller is a party or by which it is bound, or (ii)  a breach of any contract, agreement or instrument (other than contracts or agreements included as Liabilities the assignment of which to Purchaser requires the consent of a third party which consent is obtained by Seller prior to Closing) to which Seller is a party or by which Seller is bound relating to the Assets or the Liabilities, or constitute an event which with the lapse of time or action by a third party could result in a default under any of the foregoing or result in the creation of any Lien upon any of the Assets or Liabilities or materially impair Seller’s performance of its obligations hereunder or the validity or enforceability of this Agreement.

(c) The copies of all Records that have been furnished or made available to Purchaser are true, accurate and complete in all material respects.

(d) Prior to the consummation of the Transaction, Seller owns or will own a freely transferable interest in and to all of the Assets (other than those assets disposed of in the ordinary course of business of Seller), in each case, free and clear of all Liens, except as set forth in Schedule 3.1(d).

(e) There are no legal, quasi-judicial or administrative proceedings of any kind or nature now pending or, to Seller’s Knowledge, threatened against Seller before any court, government agency, administrative body or arbitrator which relate to the Assets and Liabilities and which, if adversely determined, would materially and adversely affect the Assets and Liabilities. There is no action or proceeding against and naming Seller pending or overtly threatened by written communication to Seller before any court, governmental authority or arbitrator that calls into question the validity or enforceability of this Agreement.

(f) Seller has in all material respects performed all obligations required to be performed by it to date and is not in default under, and no event has occurred which, with the lapse of time or action by a third party, could result in default under, any outstanding agreement relating to the Assets or the Liabilities and to which Seller is a party or by which Seller is bound.

(g) Except as described in Schedule 3.1(g), as of the date of this Agreement, Seller has not received any written notification of any asserted past or present failure to comply with any statutes, rules, regulations, orders, ordinances, codes, licenses, franchises, permits, authorizations, and concessions from any governmental authority or agency relating to the Assets or the Liabilities, where such failure had a material and adverse effect on the Assets or the Liabilities and such failure has not been cured or waived.

(h) Seller has not employed any broker, finder or other investment advisor or incurred any liability for any brokerage fees, commissions or finders’ fees in connection with the Transaction.

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(i) Schedule 1.1(p) sets forth as of July 31, 2007: (i)  the categories of Deposits, indicating the dollar amount of Deposits in each category and the percentage which such amount constitutes of all Deposits which are, or will be, Assumed Deposits, (ii)  the weighted average interest rate paid with respect to each such category of Deposits, and (iii)  the weighted average maturity of each such category of Deposits. All of the Records accurately reflect the transactions made as to same, and the Deposits have been administered and originated, in all material respects, in compliance with the written agreements governing the relationship between Seller and the Assumed Deposit customers and all applicable laws.

(j) With respect to the Assumed Deposits, Seller is in compliance with applicable laws and Internal Revenue Service (“ IRS ”) regulations relative to obtaining from the individuals or entities maintaining the Assumed Deposits, executed IRS Forms W-8 and W-9, or is back-up withholding on such Accounts. All information returns, reports and forms required to be furnished by Seller and any predecessor of Seller that was an Affiliate of Seller to any depositor or to any taxing authority with respect to the Assets or Liabilities have been or will be furnished to such depositors or such taxing authority within the time required by applicable law.

3.2 Representations and Warranties of Purchaser . Purchaser represents and warrants to Seller, as of the date of this Agreement and as of the Closing Date, that:

(a) Purchaser is validly existing as a federal savings bank and in good standing under the laws of the United States. The execution and delivery by Purchaser of this Agreement and the Purchaser Closing Documents and the consummation by Purchaser of its obligations hereunder are within Purchaser’s power as a federal savings bank, and have been duly authorized by all necessary corporate action on the part of Purchaser. This Agreement has been duly executed and delivered by Purchaser and constitutes Purchaser’s valid and binding obligation, subject to all Requisite Governmental Approvals, enforceable against Purchaser in accordance with its terms, except as limited by bankruptcy, receivership, conservatorship, insolvency, reorganization, fraudulent transfer, moratorium and similar laws affecting creditors generally and by the availability of equitable remedies. The Purchaser Closing Documents and the Transfer Instruments (to the extent required to be executed by Purchaser), when executed and delivered by Purchaser, will constitute valid and binding obligations of Purchaser, subject to obtaining all Requisite Governmental Approvals, enforceable in accordance with their respective terms, except as limited by bankruptcy, receivership, conservatorship, insolvency, reorganization, fraudulent transfer, moratorium and similar laws affecting creditors generally and by the availability of equitable remedies.

(b) The execution and delivery by Purchaser of this Agreement do not, and the consummation by Purchaser of its obligations hereunder will not, result in (i)  any violation by Purchaser of (A)  its charter documents or bylaws, or (B)  any order, writ, judgment or decree of any federal or state court or governmental authority or regulatory body having jurisdiction over Purchaser to which Purchaser is a party or by which it is bound, or (ii)  a breach of any contract, agreement or instrument, or loan to which Purchaser is a party or by which Purchaser is bound, or constitute an event which with the lapse of time or action by a third party could result in a default under any of the foregoing or result in the creation of any Lien upon any of the assets or properties of Purchaser or materially impair Purchaser’s performance of its obligations hereunder or the validity or enforceability of this Agreement.

(c) There are no legal, quasi-judicial or administrative proceedings of any kind or nature now pending or, to Purchaser’s Knowledge, threatened against Purchaser before any court, government agency, administrative body or arbitrator which could have a material adverse effect on the business or financial condition of Purchaser or which could reasonably be expected to prevent or impair the ability of Purchaser to perform its obligations hereunder in any material respect. There is

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no action or proceeding against and naming Purchaser pending or overtly threatened by written communication to Purchaser before any court, governmental authority or arbitrator that calls into question the validity or enforceability of this Agreement. Purchaser is not bound by any order or agreement which would preclude Purchaser from obtaining all Requisite Governmental Approvals (in a timely fashion), and, to Purchaser’s Knowledge, no order or agreement is pending which would preclude Purchaser’s consummation of the Transaction.

(d) Purchaser has advised Purchaser’s Regulatory Agency of the Transaction and has not received any indication, in writing or otherwise, that any Regulatory Agency would oppose or not issue its consent or approval, if required, with respect to the Transaction, or impose any condition to such approval that Purchaser in good faith would determine to be materially burdensome upon the business of Purchaser or upon the consummation of the Transaction.

(e) Purchaser has not employed any broker, finder or other investment advisor or incurred any liability for any brokerage fees, commissions or finders’ fees in connection with the Transaction.

(f) Purchaser’s ability to consummate the Transaction is not contingent on raising any equity capital, obtaining specific financing therefor, consent of any lender or other matter.

(g) Purchaser is not required to obtain approval of this Agreement and the Transaction by the holder(s) of outstanding securities of Purchaser.

(h) Holding Company has committed to the OTS that for a three-year period beginning January 8, 2007 it will maintain Purchaser’s capital at a level which will allow Purchaser to be classified as a “Well Capitalized” institution, as defined in regulations promulgated by the OTS for Prompt Corrective Action purposes. Purchaser is currently a “Well Capitalized” institution and will remain so on a pro forma basis giving effect to the Transaction, with additional paid-in capital to be contributed to Purchaser by Holding Company on an as-needed basis.

ARTICLE IV. transitional Matters

4.1 General Pre-Closing Covenants of Seller . In addition to performing other covenants set forth in this Agreement, from the date hereof until the Closing Date, Seller shall (a)  deliver each month to Purchaser a month-end trial balance of the Assets and Deposits and rate sheets showing deposit and loan rates offered in the Network during the prior month; (b)  carry on the business, including marketing and advertising practices, relating to the Assets and Liabilities in the usual and ordinary course and consistent with past practices (which may include changes in interest rates paid on Deposits) substantially in the same manner as heretofore carried on; (c)  maintain the Records relating to the Assets and Liabilities in a full and competent manner, consistent with past practices; (d)  comply in all material respects with all laws applicable to Seller and the conduct of its business as it relates to the Assets and Liabilities; (e)  not sell, transfer or otherwise dispose of any of the Assets or Liabilities except for such dispositions in the ordinary course of its business and consistent with past practice; and (f)  neither make nor suffer to exist any Lien on any of the Assets.

4.2 Operational Matters . No later than forty-five (45) calendar days prior to the Conversion Date, Seller will provide Purchaser with data files sufficient to produce and issue new ATM and debit cards to cardholders whose Deposit accounts are included in the Liabilities, in time for new cards to be issued to the cardholders as of the Conversion Date. In addition, Seller will not open new accounts of any type originated by the Network within three (3) days prior to the Closing Date and will cancel all its debit cards and ATM cards for Deposit customers as of the close of business on the Conversion Date.

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4.3 Inspection . Purchaser and its authorized representatives shall have reasonable access during normal business hours to all Records and other documents reasonably relating to the Assets and Liabilities, and Seller shall furnish or cause to be furnished to Purchaser and its authorized representatives all information reasonably related to the Assets and Liabilities as Purchaser may reasonably request. Notwithstanding the foregoing, Seller shall not be required to provide access to or disclose information where such access or disclosure would impose an unreasonable burden on Seller or any employee of Seller, would materially disrupt Seller’s operations or would violate or prejudice the rights of customers, jeopardize any attorney-client privilege or contravene any law, rule, regulation, order, judgment, decree, fiduciary duty or binding agreement entered into prior to the date of this Agreement. The parties hereto shall make appropriate substitute disclosure arrangements under circumstances under which the restrictions of the preceding sentence apply.

4.4 Applications . As soon as practicable and in no event later than thirty (30) calendar days after the date of this Agreement, Seller and Purchaser shall prepare and file any necessary notices or applications with any Regulatory Agency the delivery of notice to which or the approval