AMENDED AND RESTATED CREDIT AGREEMENT

Exhibit 10.1

AMENDED AND RESTATED CREDIT AGREEMENT

          THIS AMENDED AND RESTATED CREDIT AGREEMENT is made and entered into this 28 ^th day of July, 2006 by and between ENTERPRISE FINANCIAL SERVICES CORP., a Delaware corporation (the “ Borrower ”), and U.S. BANK NATIONAL ASSOCIATION , a national banking association (the “ Lender ”).

WITNESSETH :

          WHEREAS, the Borrower desires to borrow from the Lender, (i) the amount of ELEVEN MILLION AND NO/100 DOLLARS ($11,000,000.00) in the form of a revolving credit loan to finance Borrower’s working capital requirements (the “ Revolving Credit Facility ”) and (ii) the amount of FOUR MILLION AND NO/100 DOLLARS ($4,000,000.00) in the form of a term loan to finance Borrower’s acquisition of NorthStar Bancshares, Inc. (the “ Term Credit Facility ” and, together with the Revolving Credit Facility, the “ Credit Facilities ”).

          WHEREAS, the Lender is willing to provide the Credit Facilities, subject to the terms and conditions set forth herein.

          NOW THEREFORE, in consideration of mutual agreements set forth below, the Borrower and the Lender agree as follows:

          SECTION 1. DEFINITIONS

          1.1           Defined Terms .  As used in this Agreement, the following terms have the following meanings:

          “ Adjusted LIBOR Rate ” shall mean, for the applicable Loan, the per annum rate of interest equal to the sum of (a) the Daily Reset LIBOR Rate or the LIBOR Rate for the applicable Loan Period (as applicable) plus (b) 1.25%.

          “ Agreement ” shall mean this Amended and Restated Credit Agreement, as amended, supplemented or modified from time to time.

          “ Business Day ” shall mean a day other than a Saturday, Sunday or other day on which the Lender is not open to the public for carrying on substantially all of its banking functions; provided , however , that, for purposes of determining the Daily Reset LIBOR Rate, the LIBOR Rate or an applicable Loan Period for a Loan, references to Business Day shall mean any day (other than Saturday or Sunday) on which commercial banks are open for business in New York, New York.

          “ Code ” shall mean the Internal Revenue Code of 1986, as amended from time to time, and the regulations thereunder.

          “ Contingent Obligation ” shall mean as to any Person, any obligation of such Person guaranteeing or otherwise becoming legally obligated for any Indebtedness, leases, dividends or other obligations (“ primary obligations ”) of any other Person (the “ primary obligor ”) in any

manner, whether directly or indirectly, including, without limitation, any obligation of such Person, whether or not contingent (a) to purchase any such primary obligation or any property constituting direct or indirect security therefor, (b) to advance or supply funds (i) for the purchase or payment of any such primary obligation or (ii) to maintain working capital or equity capital of the primary obligor or otherwise to maintain the net worth or solvency of the primary obligor, (c) to purchase property, securities or services primarily for the purpose of assuring the owner of any such primary obligation of the ability of the primary obligor to make payment of such primary obligation or (d) otherwise to assure or hold harmless the owner of such primary obligation against loss in respect thereof.

          “ Contractual Obligation ” shall mean as to any Person, any provision of any security issued by such Person or of any agreement, instrument or undertaking to which such Person is a party or by which it or any of its property is bound.

          “ Daily Reset LIBOR Loan ” shall mean a Loan that accrues interest based upon the Daily Reset LIBOR Rate as an index.

          “ Daily Reset LIBOR Rate ” shall mean the one-month LIBOR rate quoted by Lender from Telerate Page 3750 or any successor thereto, which shall be that one-month LIBOR rate in effect and reset each Business Day, adjusted for any reserve requirement and any subsequent costs arising from a change in government regulation.  The Lender’s internal records of applicable interest rates shall be determinative in the absence of manifest error.

          “ Default Rate ” shall mean the rate per annum which is three percent (3%) per annum in excess of the then Adjusted LIBOR Rate.

          “ Environment ” shall mean any water, including, but not limited to, surface water and ground water or water vapor, any land, including land surface or subsurface, stream sediments, air, fish, wildlife, plants; and all other natural resources or environmental media.

          “ Environmental Laws ” shall mean all federal, state and local environmental, land use, zoning, health, chemical use, safety and sanitation laws, statutes, ordinances, regulations, codes and rules relating to the protection of the Environment and/or governing the use, storage, treatment, generation, transportation, processing, handling, production or disposal of hazardous substances, petroleum and petroleum products and the policies, guidelines, procedures, interpretations, decisions, orders and directives of federal, state and local governmental agencies and authorities with respect thereto.

          “ Event of Default ” shall mean any of the events specified in Section 8, provided that any requirement for the giving of notice, the lapse of time, or both, or any other condition, has been satisfied.

          “ Funding Date ” means any Business Day designated by the Borrower as a day on which (a) a Revolving Loan is to be made or (b) a Loan Period is to be renewed or extended, each in accordance with the terms and conditions of this Agreement.

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          “ Governmental Authority ” shall mean any nation or government, any state or other political subdivision thereof, and any entity exercising executive, legislative, judicial, regulatory or administrative functions of or pertaining to government.

          “ Governmental Regulations ” means any and all laws, statutes, ordinances, rules, regulations, judgments, writs, injunctions, decrees, orders, awards and standards, or any similar requirement, of the government of the United States or any foreign government or any state, province, municipality or other political subdivision thereof or therein or any court, agency, instrumentality, regulatory authority or commission of any of the foregoing.

          “ Hedge Agreement ” means any agreement between the Borrower and the Lender or any affiliate of the Lender now existing or hereafter entered into, which provides for an interest rate or commodity swap, cap, floor, collar, forward foreign exchange transaction, currency swap, cross-currency rate swap, currency option, or any combination of, or option with respect to, these or similar transactions as contemplated under this Credit Agreement, for the purpose of hedging a Borrower’s exposure to fluctuations in interest rates, currency valuations or commodity prices.

          “ Indebtedness ” shall mean as to any Person, at a particular time, (a) indebtedness for borrowed money or for the deferred purchase price of property or services in respect of which such Person is an obligor and (b) obligations under leases which shall have been or should be, in accordance with generally accepted accounting principles (“ GAAP ”) and/or tax-basis accounting, consistently applied, recorded as capital leases in respect of which obligations such Person is liable.

          “ Interest Differential ” shall mean that sum equal to the greater of zero or the financial loss incurred by Lender resulting from prepayment, calculated as the difference between the amount of interest Lender would have earned (from like investments in the Money Markets as of the first day of the LIBOR Loan) had prepayment not occurred and the interest Lender will actually earn (from like investments in Money Markets as of the date of prepayment) as a result of the redeployment of funds from such prepayment.  The Interest Differential shall not be discounted to its present value.

          “ LIBOR Loans ” shall mean a Loan which accrues interest based upon the LIBOR Rate as an index.

          “ LIBOR Rate ” means the one, two or three month LIBOR rate quoted by Lender from Telerate Page 3750 or any successor thereto (which shall be the LIBOR Rate in effect two Business Days prior to commencement of the applicable Loan), adjusted for any reserve requirement and any subsequent costs arising from a change in government regulation.  The Lender’s internal records of applicable interest rates shall be determinative in the absence of manifest error.

          “ Lien ” shall mean any mortgage, pledge, hypothecation, assignment, deposit arrangement, encumbrance, lien (statutory or other), or preference, priority or other security agreement or preferential arrangement of any kind or nature whatsoever (including, without limitation, any conditional sale or other title retention agreement, and any financing lease having substantially the same economic effect as any of the foregoing).

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          “ Loan ” shall mean an advance of loan proceeds made by the Lender to the Borrower pursuant to the Revolving Note or the Term Note and this Agreement and “Loans” shall collectively refer to all such advances.

          “ Loan Documents ” shall mean this Agreement, the Revolving Note, the Term Note, any Hedge Agreement and all other documents, certificates, resolutions and other agreements executed by the Borrower or any other party pursuant to or in connection with this Agreement.

          “ Loan Period ” means, with respect to each LIBOR Loan, the period commencing on the Funding Date for such Loan and ending on the numerically corresponding day one (1) month, two (2) month or three (3) months thereafter matching the interest rate term selected by Borrower in the Notice of Borrowing submitted under Section 2.4; provided, however, that:

          a.          if any Loan Period would otherwise end on a day which is not a Business Day, then the Loan Period shall end on the next succeeding Business Day unless the next succeeding Business Day falls in another calendar month, in which case the Loan Period shall end on the immediately preceding Business Day;

          b.          if any Loan Period begins on the last Business Day of a calendar month (or on a day for which there is no numerically corresponding day in the calendar month at the end of such Loan Period) then the Loan Period shall end on the last Business Day of the calendar month at the end of such Loan Period;

          c.          any Loan Period which would otherwise end after the Termination Date shall end on the Termination Date; and

          d.          the interest rate applicable to any Loan Period shall apply from and include the first day of such Loan Period to but excluding the last day of such Loan Period.

          “ Notes ” shall mean, collectively, the Revolving Note and the Term Note. 

          “ Person ” shall mean an individual, partnership, corporation, business trust, joint stock trust, unincorporated association, joint venture, Governmental Authority or other entity of whatever nature.

          “ Prime Rate ” means the prime or base rate of interest as announced by the Lender, as in effect from time to time, which rate may not be the lowest rate charged by the Lender to any of its customers, and which Prime Rate shall change simultaneously with any change in such prime or base rate of interest.

          “ Revolving Credit Commitment ” shall mean $11,000,000.00.

          “ Revolving Credit Termination Date ” shall mean April 30, 2007.

          “ Revolving Note ” shall mean the Amended and Restated Revolving Credit Note of even date herewith in the face amount of $11,000,000.00 from the Borrower, as maker, payable to the Lender, substantially in the form of Exhibit A .

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          “ Requirements of Law ” shall mean as to any Person, the Articles of Incorporation and Bylaws or other organizational or governing documents of such Person, and any law, treaty, rule or regulation, or determination of any arbitrator or a court or other Governmental Authority, in each case applicable to or binding upon such Person or any of its property or to which such Person or any of its property is subject.

          “ Solvent ” shall mean, with respect to any Person on a particular determination date, that on such date (i) the fair value of the property of such Person is greater than the total amount of debts and other liabilities, including, without limitation, contingent and unliquidated liabilities, of such Person, (ii) such Person is able to realize upon its assets and pay its debts and other liabilities, contingent obligations and other commitments as they mature in the normal course of business, and (iii) such Person does not intend to, and does not believe that it will, incur debts or other liabilities beyond such Person’s ability to pay as such debts and other liabilities mature or become due.

          “ Subsidiary ” of any Person shall mean any other Person (whether now existing or hereafter organized or acquired) in which at least a majority of the securities or other ownership interests of each class having ordinary voting power or analogous rights of such other Person are owned (other than securities or other ownership interests which at the time as of which any determination is being made, are owned or have such power or right only by reason of the happening of a contingency), beneficially and of record, by such Person or by one or more of the other Subsidiaries of such Person or by any combination thereof.

          “ Subsidiary Bank ” shall mean Enterprise Bank & Trust, a Missouri trust company.

          “ Subsidiary Brokerage ” shall mean Millennium Holding Company, Inc., a Missouri corporation.

          “ Term Credit Commitment ” shall mean $4,000,000.00.

          “ Term Note ” shall mean the Promissory Note of even date herewith in the face amount of $4,000,000.00 from the Borrower, as maker, payable to the Lender, substantially in the form of Exhibit B .

          “ Term Credit Termination Date ” shall mean July 28, 2009.

          1.2       Other Definition Provisions .

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          SECTION 2.   AMOUNT AND TERMS OF REVOLVING LOAN

          2.1           Revolving Loan .  The Revolving Credit Facility shall be evidenced by the Revolving Note. Subject to the terms and conditions of this Agreement, the Lender agrees to make Loans to the Borrower from time to time from and including the date hereof to but excluding the Revolving Credit Termination Date, up to, but not exceeding at any time the Revolving Credit Commitment; provided , however , that the Lender shall have no obligation to make a Loan if an Event of Default exists or would result from such Loan.  Loans may be outstanding as Daily Reset LIBOR Loans or LIBOR Loans (each, a “ Type of Loan ”). Within the limits of the Revolving Credit Commitment and subject to the other terms and conditions of this Agreement, under the Revolving Credit Facility may be borrowed, repaid and reborrowed by the Borrower, in its discretion, from time to time prior to the Revolving Credit Termination Date.  The Lender may, with three (3) Business Days prior notice to or the consent of Borrower, to pay any principal due under the Revolving Credit Facility, any interest due thereon or any fees, cash or expenses due from Borrower to the Lender under this Agreement.

          2.2           Principal Payments .  Unless earlier payment is required under this Agreement, the Revolving Credit Facility shall be due and payable to the Lender on or before the Revolving Credit Termination Date.  If at any time the outstanding principal amount of the Revolving Credit Facility made by the Lender shall exceed the Revolving Credit Commitment, the Borrower shall forthwith pay to the Lender an amount not less than the amount of any such excess for application to the outstanding principal amount of the Revolving Credit Facility.  If the Loan Period for any LIBOR Loan should happen to extend beyond the Revolving Credit Facility Termination Date, such LIBOR Loan must be prepaid on the Revolving Facility Termination Date.

          2.3           Interest .

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          2.4           Borrowings .  In order to obtain a Loan under the Revolving Credit Facility, the Borrower shall give the Lender written notice (which may be a telecopy) of each borrowing to be made hereunder.  Each such notice shall be in the form of a “Notice of Borrowing” in substantially the form of Exhibit C hereto, executed by two authorized officers or representatives of the Borrower, specifying therein (i) the requested date of the proposed Loan, (ii) the aggregate amount of the proposed Loan, and (iii) if a LIBOR Loan, the Loan Period therefor.  Subject to the conditions of this Agreement, the Lender shall make the amount of the Loan available to the Borrower on the date of such Loan in immediately available funds.  

          2.5           Prepayments and Conversions .  Subject to Section 4.3 hereof, the Borrower shall have the right to make prepayments of principal on any Loan, in whole or in part, without payment of any penalty or premium, or to convert one Type of Loan into another Type of Loan, at any time or from time to time; provided , however , that each partial prepayment shall be in an amount of at least $100,000, and if greater than $100,000, an integral multiple of $10,000.00, and if the Loan prepaid or converted is a LIBOR Loan, any conversion or prepayment shall be in the full amount of such LIBOR Loan. The Borrower shall give the Lender notice of each such prepayment or conversion as provided in Section 2.9. Each such notice shall be in the form of a “Notice of Prepayment” in substantially the form of Exhibit C hereto, specifying therein (i) the date such prepayment will be made, (ii) the amount of such prepayment and (iii) the Type of Loan being prepaid.  The Borrower shall not have the right to convert one Type of Loan into another Type of Loan during the continuance of an Event of Default.

          2.6           Loan Periods; Renewals .

          2.7           Default Rate .  If an “Event of Default” as defined in Section 1.1 shall have occurred and be continuing, the Borrower shall pay interest at the Default Rate.  In no event shall the rate of interest exceed the maximum rate permitted by applicable law.  If the Borrower pays to the Lender interest in excess of the amount permitted by applicable law, such excess shall be applied in reduction of the principal balance of the Credit Facilities (as the Lender may elect), and any remaining excess interest, after application thereof to the principal balance of the Credit Facilities, shall be refunded to the Borrower.

          2.8           Payments .  All payments (including prepayments) by the Borrower on account of principal, interest and fees shall be made without set-off or counterclaim to the Lender at its office referred to in Section 10.2 in lawful money of the United States of America and in immediately available funds.

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          2.9           Certain Notices .  Notices by the Borrower to the Lender pursuant to Section 2.4, each prepayment pursuant to Section 2.5 and each renewal pursuant to Section 2.6(b) shall be irrevocable and shall be effective only if received by the Lender not later than 10:00 a.m. St. Louis, Missouri time, and (a) in the case of borrowings and prepayments of, conversions into and (in the case of LIBOR Loans) renewals of (i) Daily Reset LIBOR Loans, given on the Business Day thereof; and (ii) LIBOR Loans, given two (2) Business Days prior thereto.  Each such notice shall specify the Loans to be borrowed, prepaid, converted or renewed and the amount (subject to Section 2.10) and Type of Loans to be borrowed, converted, prepaid or renewed (and in the case of conversion, the Type of Loans to result from such conversion and in the case of LIBOR Loans, the Loan Period therefor) and the date of the borrowing, prepayment, conversion or renewal (which shall be a Business Day), in the case of a borrowing, such additional information as may be required by Section 2.4.

          2.10           Minimum Amounts .  Each Daily Reset LIBOR Loan (or Prime Rate Loan) shall be in the minimum amount of $50,000.00, and if greater than $50,000.00, an integral multiple of $5,000. Each LIBOR Loan shall be in the minimum amount of $100,000, and if greater than $100,000, an integral multiple of $10,000.  In addition, there shall be no more than ten (10) LIBOR Loans under the Revolving Credit Facility outstanding at any time.

          2.11           Use of Proceeds .  The proceeds of the Loans described herein shall be used by the Borrower to finance general working capital purposes of the Borrower and to make capital investments from time to time in the Subsidiary Bank.

          SECTION 3.   AMOUNT AND TERMS OF TERM CREDIT FACILITY

          3.1           Term Loan .  The Term Credit Facility shall be evidenced by the Term Note.  Subject to the terms and conditions of this Agreement, the Lender agrees to make the Term Credit Facility to the Borrower up to, but not exceeding at any time the Term Credit Facility Commitment; provided , however , that the Lender shall have no obligation to provide the Term Credit Facility if an Event of Default exists as of the date of this Agreement.  The Term Credit Facility may be outstanding as a Daily Reset LIBOR Loan or LIBOR Loan Credit Facility.

          3.2           Principal Payments .  Unless earlier payment is required under this Agreement, the Term Credit Facility shall be due and payable to the Lender on the Term Credit Facility Termination Date.

          3.3           Incorporation of Terms .  The provisions contained in Sections 2.3, 2.5, 2.6, 2.7, 2.8 and 2.9 shall apply to the Term Credit Facility and such provisions are hereby incorporated within this Section 3.3 by this reference; provided , however , notwithstanding such incorporated provisions, only one Loan and Type of Loan may be outstanding under the Term Credit Facility at any time.

          3.4           Use of Proceeds .  The proceeds of the Term Credit Facility described herein shall be used by the Borrower to finance the acquisition by Borrower of NorthStar Bancshares, Inc.

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          SECTION 4.   YIELD PROTECTION; ILLEGALITY; ETC.

          4.1           Additional Costs .  If the Lender shall determine in good faith that any Governmental Regulation not presently in effect or applicable to the Lender, or any interpretation or administration thereof by any governmental authority charged with the interpretation or administration thereof, or compliance by the Lender with any new guideline, request or directive of any such authority (whether or not having the force of law), shall (i) affect the basis of taxation of payments to the Lender of any amounts payable by the Borrower under this Agreement or any other Loan Document (other than taxes imposed on the overall net income of the Lender, by the jurisdiction, or by any political subdivision or taxing authority of any such jurisdiction, in which the Lender has its principal office), or (ii) impose, modify or deem applicable any reserve, special deposit or similar requirement against assets of, deposits with or for the account of, or credit extended by the Lender, or (iii) impose any other condition with respect to this Agreement, the Commitment, the Loans, and the result of any of the foregoing is to increase by an amount deemed by the Lender to be material the costs to the Lender of providing the Commitment or making, funding or maintaining the Loans or to reduce by an amount deemed by the Lender to be material the amount of any sum receivable by the Lender under this Agreement, then the Borrower shall pay to the Lender, such additional amounts as are sufficient to compensate the Lender for such increased cost or reduced sum receivable. A statement as to the amount of such increased cost or reduced sum receivable, prepared in good faith and in reasonable detail by the Lender and submitted to the Borrower, shall be conclusive and binding for all purposes absent manifest error in computation.

          4.2           Illegality and Impossibility .

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          4.3           LIBOR Rate Indemnity .  If the Borrower fails to make any payment of principal or interest in respect of any Loan based upon a LIBOR Rate when due or makes any payment or prepayment of the principal of any such Loan, for any reason, on any date other than the last day of the Loan Period applicable thereto, or if the Borrower fails to borrow any Loan based upon the LIBOR Rate after requesting the same in accordance with this Agreement, the Borrower shall reimburse the Lender on demand for any resulting loss or expense incurred by the Lender, including any loss incurred in obtaining, liquidating or employing deposits from third parties.  A statement as to the amount of such loss or expense, prepared in good faith and in reasonable detail by the Lender and submitted to the Borrower, shall be conclusive and binding for all purposes absent manifest error in computation.  Without limiting the foregoing, if a LIBOR Loan is prepaid prior to the end of the Loan Period for such LIBOR Loan, whether voluntarily or because prepayment is required due to the occurrence of the Termination Date or on account of a default, Borrower agrees to pay all of Lender’s costs, expenses and Interest Differential, as determined by Lender, incurred as a result of such prepayment.

          SECTION 5.   REPRESENTATIONS AND WARRANTIES

          In order to induce the Lender to enter into this Agreement and to make each Loan herein provided for, the Borrower hereby represents and warrants to the Lender (for itself and on behalf of the Subsidiary Bank where applicable) that:

          5.1           Financial Condition .

          5.2           No Change .  Since December 31, 2005, there has been no material adverse change in the business, operations, assets or financial or other condition of the Borrower.

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          5.3           Existence; Compliance with Law .  The Borrower (a) is duly organized, validly existing and in good standing under the laws of the jurisdiction of its organization, (b) has the power and authority and the legal right to own and operate its property, to lease the property it operates and to conduct the business in which it is currently engaged, (c) is duly qualified as a foreign entity and is in good standing under the laws of each jurisdiction where ownership, lease or operation of property or the conduct of its business requires such qualification except to the extent that the failure to comply therewith would not, in the aggregate, have a material adverse impact on its business operations, property or financial or other condition and would not materially adversely affect the ability of the Borrower to perform its obligations under this Agreement, and (d) is in compliance with all Requirements of Law except to the extent that the failure to comply therewith would not, in the aggregate, have a material adverse effect on its business, operations, property or financial or other condition and would not materially adversely affect the ability of the Borrower to perform its obligations under this Agreement.

          5.4           Authorization; Enforceable Obligations .  The Borrower has the power and authority and the legal right to make, deliver and perform this Agreement, the Revolving Note, the Term Note and the Loan Documents to be executed by Borrower.  No consent o