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                                                                    EXHIBIT 4.10

                              DECLARATION OF TRUST
                                       OF
                           REGIONS FINANCING TRUST III

         This Declaration of Trust, dated as of November 20, 2001 (this
"Declaration"), is entered into by and among Regions Financial Corporation, a
Delaware corporation, as depositor (the "Depositor"), Bankers Trust Company, a
New York banking corporation, as trustee, and Bankers Trust (Delaware), a
Delaware banking corporation, as trustee (collectively, the "Trustees"). The
Depositor and the Trustees hereby agree as follows:

         (1)      The trust created hereby (the "Trust") shall be known as
"Regions Financing Trust III," in which name the Trustees or the Depositor, to
the extent provided herein, may conduct the business of the Trust, make and
execute contracts, and sue and be sued.

         (2)      The Depositor hereby assigns, transfers, conveys and sets over
to the Trust the sum of ten dollars ($10.00). The Trustees hereby acknowledge
receipt of such amount from the Depositor, which amount shall constitute the
initial trust estate. The Trustees hereby declare that they will hold the trust
estate for the Depositor. It is the intention of the parties hereto that the
Trust created hereby constitute a business trust under Chapter 38 of Title 12 of
the Delaware Code, 12 Del. C. ss. 3801 et seq. (the "Business Trust Act"), and
that this document constitutes the governing instrument of the Trust. The
Trustees are hereby authorized and directed to execute and file a certificate of
trust with the Secretary of State of the State of Delaware.

         (3)      The Depositor and the Trustees will enter into an amended and
restated declaration of trust (the "Amended and Restated Declaration of Trust")
satisfactory to each such party to provide for the contemplated operation of the
Trust created hereby and the issuance of the preferred securities representing
undivided beneficial interests in the assets of the Trust and common securities
representing undivided beneficial interests in the assets of the Trust. Prior to
the execution and delivery of such Amended and Restated Declaration of Trust,
the Trustees shall not have any duty or obligation hereunder or with respect to
the trust estate, except as otherwise contemplated by this Declaration, required
by applicable law or as may be necessary to obtain prior to such execution and
delivery any licenses, consents or approvals required by applicable law or
otherwise. Notwithstanding the foregoing, the Trustees may take all actions
deemed proper or as are necessary to effect the transactions contemplated
herein.

         (4)      The Depositor, as depositor of the Trust, is hereby
authorized, in its sole discretion, (i) to prepare and file with the Securities
and Exchange Commission (the "Commission") and to execute, in the case of the
1933 Act Registration Statement and 1934 Act Registration Statement (as herein
defined), on behalf of the Trust, (a) a Registration Statement (the "1933 Act
Registration Statement"), including all pre-effective and post-effective
amendments thereto, relating to the registration under the Securities Act of
1933, as amended (the "1933 Act"), of the preferred securities of the Trust, (b)
any preliminary prospectus or prospectus or supplement thereto relating to the
preferred securities of the Trust required to be filed pursuant to the 1933 Act,
and (c) a Registration Statement on Form 8-A or other appropriate form (the
"1934 Act Registration Statement"), including all pre-effective and
post-effective amendments

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thereto, relating to the registration of the preferred securities of the Trust
under the Securities Exchange Act of 1934, as amended; (ii) if and at such time
as determined by the Depositor, to file with the New York Stock Exchange or
other exchange, or the National Association of Securities Dealers ("NASD"), and
execute on behalf of the Trust a listing application and all other applications,
statements, certificates, agreements and other instruments as shall be necessary
or desirable to cause the preferred securities of the Trust to be listed on the
New York Stock Exchange or such other exchange, or the NASD's Nasdaq National
Market; (iii) to file and execute on behalf of the Trust, such applications,
reports, surety bonds, irrevocable consents, appointments of attorney for
service of process and other papers and documents that shall be necessary or
desirable to register the preferred securities of the Trust under the securities
or "blue sky" laws of such jurisdictions as the Depositor, on behalf of the
Trust, may deem necessary or desirable; (iv) to execute and deliver letters or
documents to, or instruments for filing with, a depository relating to the
preferred securities of the Trust; and (v) to execute, deliver and perform on
behalf of the Trust an underwriting agreement with one or more underwriters
relating to the offering of the preferred securities of the Trust.

         In the event that any filing referred to in this Section 4 is required
by the rules and regulations of the Commission, the New York Stock Exchange,
Inc. or other exchange, NASD, or state securities or "Blue Sky" laws to be
executed on behalf of the Trust by the Trustees, the Trustees, in their capacity
as trustees of the Trust, are hereby authorized to join in any such filing and
to execute on behalf of the Trust any and all of the foregoing, it being
understood that the Trustees, in their capacity as trustees of the Trust, shall
not be required to join in any such filing or to execute on behalf of the Trust
any such document unless required by the rules and regulations of the
Commission, the New York Stock Exchange, Inc. or other exchange, NASD, or state
securities or "Blue Sky" laws.

         (5)      This Declaration may be executed in one or more counterparts.

         (6)      The number of Trustees initially shall be two (2) and
thereafter the number of Trustees shall be such number as shall be fixed from
time to time by a written instrument signed by the Depositor which may increase
or decrease the number of Trustees; provided that, to the extent required by the
Business Trust Act, one Trustee shall be an entity that has its principal place
of business in the State of Delaware. Subject to the foregoing, the Depositor is
entitled to appoint or remove without cause any Trustee at any time upon thirty
(30) days prior written notice. The Trustees may resign upon thirty days prior
notice to the Depositor.

         (7)      The Depositor hereby agrees to (i) reimburse the Trustees for
all reasonable expenses (including reasonable fees and expenses of counsel and
other experts) and (ii) indemnify, defend and hold harmless the Trustees and any
of the officers, directors, employees and agents of the Trustees (the
"Indemnified Persons") from and against any and all losses, damages,
liabilities, claims, actions, suits, costs, expenses, disbursements (including
the reasonable fees and expenses of counsel), taxes and penalties of any kind
and nature whatsoever (collectively, "Expenses"), to the extent that such
Expenses arise out of, or are imposed upon, or are asserted at any time against,
such Indemnified Persons with respect to the performance of this Declaration,
the creation, operation or termination of the Trust or the transactions
contemplated

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hereby; provided, however, that the Depositor shall not be required to indemnify
any Indemnified Person for any Expenses which are a result of the willful
misconduct, bad faith or gross negligence of such Indemnified Person.

         (8)      The Trust may be dissolved and terminated before the issuance
of the securities of the Trust at the election of the Depositor.

         (9)      This Declaration shall be governed by and construed in
accordance with the laws of the State of Delaware (without regard to conflict of
laws principles).

                            [SIGNATURE PAGE FOLLOWS]

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         IN WITNESS WHEREOF, the parties hereto have caused this Declaration of
Trust to be duly executed as of the day and year first above written.



                                       REGIONS FINANCIAL CORPORATION,
                                       as Depositor



                                       By: /s/ Samuel E. Upchurch, Jr.
                                           ----------------------------------
                                          Name: Samuel E. Upchurch, Jr.
                                          Title: Executive Vice President,
                                                 General Counsel and Secretary



                                       BANKERS TRUST COMPANY, a New
                                       York banking corporation, as trustee



                                       By: /s/ Tracy Salzman
                                           ----------------------------------
                                          Name: Tracy Salzman
                                          Title: Associate



                                       BANKERS TRUST (DELAWARE), a
                                       Delaware banking corporation, as trustee



                                       By: /s/ Elizabeth B. Ferry
                                           ----------------------------------
                                          Name: Elizabeth B. Ferry
                                          Title: Assistant Vice President