EXHIBIT 5.1

                                 July 12, 2001



The Colonial BancGroup, Inc.
One Commerce Street, Suite 800
Montgomery, Alabama 36104

         Re:   Registration Statement on Form S-8 relating to the
               The Colonial BancGroup, Inc. 2001 Long-Term Incentive Plan

Gentlemen:

         We are familiar with the proceedings taken and proposed to be taken by
The Colonial BancGroup, Inc., a Delaware corporation (the "Company"), in
connection with the proposed issuance by the Company of 10,000,000 additional
shares of its Common Stock, par value $2.50 per share, from authorized but
unissued shares pursuant to the Company's 2001 Long-Term Incentive Plan, as
amended (the "Plan"). We have also acted as counsel for the Company in
connection with the preparation and filing with the Securities and Exchange
Commission under the Securities Act of 1933, as amended, of the registration
statement on Form S-8 referred to in the caption above. In this connection, we
have reviewed such documents and matters of law as we have deemed relevant and
necessary as a basis for the opinions expressed herein.

         Upon the basis of the foregoing, we are of the opinion that:

         (i)   The Company is a corporation duly organized and existing under
the laws of the State of Delaware;

         (ii)  The shares of Common Stock of the Company referred to above, to
the extent actually issued pursuant to the Plan from the Company's authorized
but unissued shares of Common Stock, will be duly and validly authorized and
issued and will be fully paid and nonassessable shares of Common Stock of the
Company; and

         (iii) Under the laws of the State of Delaware, no personal liability
attaches to the ownership of the shares of Common Stock of the Company.


         We hereby consent to the filing of this opinion as an exhibit to the
above-referenced registration statement. In consenting to the inclusion of our
opinion in the registration statement we do not thereby admit that we are a
person whose consent is required pursuant to Section 7 of the Securities Act of
1933, as amended.

                                     Sincerely,


                                     MILLER, HAMILTON, SNIDER & ODOM, L.L.C.

                                     By: /s/ Willard H. Henson
                                        ---------------------------
                                             Willard H. Henson

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