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                                                                    Exhibit 10.6

                             FBTC STATUTORY TRUST I
                          FIRST BANCTRUST CORPORATION

                             SUBSCRIPTION AGREEMENT

                                  JUNE 15, 2005

     THIS SUBSCRIPTION AGREEMENT (this "Agreement") made among FBTC Statutory
Trust I (the "Trust"), a statutory trust created under the Delaware Statutory
Trust Act (Chapter 38 of Title 12 of the Delaware Code, 12 Del. C. Sections
3801, et seq.), First BancTrust Corporation, a Delaware corporation, with its
principal offices located at 101 South Central, Paris, Illinois 61944 (the
"Company" and, collectively with the Trust, the "Offerors"), and Preferred Term
Securities XVIII, Ltd. (the "Purchaser").

                                    RECITALS:

     A. The Trust desires to issue 6,000 of its Fixed/Floating Rate Capital
Securities (the "Capital Securities"), liquidation amount $1,000.00 per Capital
Security, representing an undivided beneficial interest in the assets of the
Trust (the "Offering"), to be issued pursuant to an Amended and Restated
Declaration of Trust (the "Declaration") by and among the Company, Wilmington
Trust Company ("WTC"), the administrators named therein, and the holders (as
defined therein), which Capital Securities are to be guaranteed by the Company
with respect to distributions and payments upon liquidation, redemption and
otherwise pursuant to the terms of a Guarantee Agreement between the Company and
WTC, as trustee (the "Guarantee"); and

     B. The proceeds from the sale of the Capital Securities will be combined
with the proceeds from the sale by the Trust to the Company of its common
securities, and will be used by the Trust to purchase an equivalent amount of
Fixed/Floating Rate Junior Subordinated Deferrable Interest Debentures of the
Company (the "Debentures") to be issued by the Company pursuant to an indenture
to be executed by the Company and WTC, as trustee (the "Indenture"); and

     C. In consideration of the premises and the mutual representations and
covenants hereinafter set forth, the parties hereto agree as follows:

                                    ARTICLE I

                     PURCHASE AND SALE OF CAPITAL SECURITIES

     1.1. Upon the execution of this Agreement, the Purchaser hereby agrees to
purchase from the Trust 6,000 Capital Securities at a price equal to $1,000.00
per Capital Security (the "Purchase Price") and the Trust agrees to sell such
Capital Securities to the Purchaser for said Purchase Price. The rights and
preferences of the Capital Securities are set forth in the Declaration. The
Purchase Price is payable in immediately available funds on June 15, 2005, or
such other business day as may be designated by the Purchaser, but in no event
later than June 30, 2005 (the "Closing Date"). The Offerors shall provide the
Purchaser wire transfer instructions no later than 1 day following the date
hereof.

     1.2. The certificate for the Capital Securities shall be delivered by the
Trust on the Closing Date to the Purchaser or its designee.

     1.3. The Placement Agreement, dated June 7, 2005 (the "Placement
Agreement"), among the Offerors and the Placement Agents identified therein
includes certain representations and warranties, covenants and conditions to
closing and certain other matters governing the Offering. The Placement

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Agreement is hereby incorporated by reference into this Agreement and the
Purchaser shall be entitled to each of the benefits of the Placement Agents and
the Purchaser under the Placement Agreement and shall be entitled to enforce the
obligations of the Offerors under such Placement Agreement as fully as if the
Purchaser were a party to such Placement Agreement.

                                   ARTICLE II

                   REPRESENTATIONS AND WARRANTIES OF PURCHASER

     2.1. The Purchaser understands and acknowledges that neither the Capital
Securities, the Debentures nor the Guarantee have been registered under the
Securities Act of 1933, as amended (the "Securities Act"), or any other
applicable securities law, are being offered for sale by the Trust in
transactions not requiring registration under the Securities Act, and may not be
offered, sold, pledged or otherwise transferred by the Purchaser except in
compliance with the registration requirements of the Securities Act or any other
applicable securities laws, pursuant to an exemption therefrom or in a
transaction not subject thereto.

     2.2. The Purchaser represents, warrants and certifies that (i) it is not a
"U.S. person" as such term is defined in Rule 902 under the Securities Act, (ii)
it is not acquiring the Capital Securities for the account or benefit of any
such U.S. person, (iii) the offer and sale of Capital Securities to the
Purchaser constitutes an "offshore transaction" under Regulation S of the
Securities Act, and (iv) it will not engage in hedging transactions with regard
to the Capital Securities unless such transactions are conducted in compliance
with the Securities Act and the Purchaser agrees to the legends and transfer
restrictions set forth on the Capital Securities certificate.

     2.3. The Purchaser represents and warrants that it is purchasing the
Capital Securities for its own account, for investment, and not with a view to,
or for offer or sale in connection with, any distribution thereof in violation
of the Securities Act or other applicable securities laws, subject to any
requirement of law that the disposition of its property be at all times within
its control and subject to its ability to resell such Capital Securities
pursuant to an effective registration statement under the Securities Act or
under Rule 144A or any other exemption from registration available under the
Securities Act or any other applicable Securities law.

     2.4. The Purchaser represents and warrants that it has full power and
authority to execute and deliver this Agreement, to make the representations and
warranties specified herein, and to consummate the transactions contemplated
herein and it has full right and power to subscribe for Capital Securities and
perform its obligations pursuant to this Agreement.

     2.5. The Purchaser, a Cayman Islands Company whose business includes
issuance of certain notes and acquiring the Capital Securities and other similar
securities, represents and warrants that it has such knowledge and experience in
financial and business matters that it is capable of evaluating the merits and
risks of purchasing the Capital Securities, has had the opportunity to ask
questions of, and receive answers and request additional information from, the
Offerors and is aware that it may be required to bear the economic risk of an
investment in the Capital Securities.

     2.6. The Purchaser represents and warrants that no filing with, or
authorization, approval, consent, license, order, registration, qualification or
decree of, any governmental body, agency or court having jurisdiction over the
Purchaser, other than those that have been made or obtained, is necessary or
required for the performance by the Purchaser of its obligations under this
Agreement or to consummate the transactions contemplated herein.


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     2.7. The Purchaser represents and warrants that this Agreement has been
duly authorized, executed and delivered by the Purchaser.

     2.8. The Purchaser represents and warrants that (i) the Purchaser is not in
violation or default of any term of its Memorandum of Association or Articles of
Association, of any provision of any mortgage, indenture, contract, agreement,
instrument or contract to which it is a party or by which it is bound or of any
judgment, decree, order, writ or, to its knowledge, any statute, rule or
regulation applicable to the Purchaser which would prevent the Purchaser from
performing any material obligation set forth in this Agreement; and (ii) the
execution, delivery and performance of and compliance with this Agreement, and
the consummation of the transactions contemplated herein, will not, with or
without the passage of time or giving of notice, result in any such material
violation, or be in conflict with or constitute a default under any such term,
or the suspension, revocation, impairment, forfeiture or non-renewal of any
permit, license, authorization or approval applicable to the Purchaser, its
business or operations or any of its assets or properties which would prevent
the Purchaser from performing any material obligations set forth in this
Agreement.

     2.9. The Purchaser represents and warrants that the Purchaser is an
exempted company with limited liability duly incorporated, validly existing and
in good standing under the laws of the jurisdiction where it is organized, with
full power and authority to perform its obligations under this Agreement.

     2.10. The Purchaser understands and acknowledges that the Company will rely
upon the truth and accuracy of the foregoing acknowledgments, representations,
warranties and agreements and agrees that, if any of the acknowledgments,
representations, warranties or agreements deemed to have been made by it by its
purchase of the Capital Securities are no longer accurate, it shall promptly
notify the Company.

     2.11. The Purchaser understands that no public market exists for any of the
Capital Securities, and that it is unlikely that a public market will ever exist
for the Capital Securities.

                                   ARTICLE III

                                  MISCELLANEOUS

     3.1. Any notice or other communication given hereunder shall be deemed
sufficient if in writing and sent by registered or certified mail, return
receipt requested, international courier or delivered by hand against written
receipt therefor, or by facsimile transmission and confirmed by telephone, to
the following addresses, or such other address as may be furnished to the other
parties as herein provided:

          To the Offerors:  First BancTrust Corporation
                            101 South Central
                            Paris, Illinois 61944
                            Attention: Terry J. Howard
                            Fax: 217-465-0235

          To the Purchaser: Preferred Term Securities XVIII, Ltd.
                            c/o Maples Finance Limited
                            P.O. Box 1093 GT
                            Queensgate House
                            South Church Street
                            George Town, Grand Cayman
                            Cayman Islands
                            Attention: The Directors
                            Fax: 345-945-7100


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          Unless otherwise expressly provided herein, notices shall be deemed to
have been given on the date of mailing, except notice of change of address,
which shall be deemed to have been given when received.

     3.2. This Agreement shall not be changed, modified or amended except by a
writing signed by the parties to be charged, and this Agreement may not be
discharged except by performance in accordance with its terms or by a writing
signed by the party to be charged.

     3.3. Upon the execution and delivery of this Agreement by the Purchaser,
this Agreement shall become a binding obligation of the Purchaser with respect
to the purchase of Capital Securities as herein provided.

     3.4. NOTWITHSTANDING THE PLACE WHERE THIS AGREEMENT MAY BE EXECUTED BY ANY
OF THE PARTIES HERETO, THE PARTIES EXPRESSLY AGREE THAT ALL THE TERMS AND
PROVISIONS HEREOF SHALL BE CONSTRUED IN ACCORDANCE WITH AND GOVERNED BY THE LAWS
OF THE STATE OF NEW YORK, WITHOUT REGARD TO PRINCIPLES OF CONFLICTS OF LAW.

     3.5. The parties agree to execute and deliver all such further documents,
agreements and instruments and take such other and further action as may be
necessary or appropriate to carry out the purposes and intent of this Agreement.

     3.6. This Agreement may be executed in one or more counterparts each of
which shall be deemed an original, but all of which shall together constitute
one and the same instrument.

     3.7. In the event that any one or more of the provisions contained herein,
or the application thereof in any circumstances, is held invalid, illegal or
unenforceable in any respect for any reason, the validity, legality and
enforceability of any such provision in every other respect and of the remaining
provisions hereof shall not be in any way impaired or affected, it being
intended that all of the Offerors' and the Purchaser's rights and privileges
shall be enforceable to the fullest extent permitted by law.

                     Signatures appear on the following page


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     IN WITNESS WHEREOF, I have set my hand the day and year first written
above.

PREFERRED TERM SECURITIES XVIII, LTD.


By: /s/ Carrie Bunton
    ---------------------------------
Print Name: Carrie Bunton
Title: Director

     IN WITNESS WHEREOF, this Agreement is agreed to and accepted as of the day
and year first written above.

                                        FIRST BANCTRUST CORPORATION


                                        By: /s/ Terry J. Howard
                                            ------------------------------------
                                        Name: Terry J. Howard
                                        Title: President & CEO


                                        FBTC STATUTORY TRUST I


                                        By: /s/ Terry J. Howard
                                            ------------------------------------
                                        Name: Terry J. Howard
                                        Title: Administrator


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