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                                                                    Exhibit 10-a



[AMSOUTH LETTERHEAD]



                               December 13, 1999

Personal and Confidential
-------------------------

Thomas E. Hoaglin
101 East Columbus Street
Columbus, OH 43206

Via Facsimile 614-449-2182

Dear Tom:

     This will confirm our offer to you to become Vice Chairman of AmSouth
Bancorporation and AmSouth Bank.

Position

     Your title would be Vice Chairman of AmSouth Bancorporation and of AmSouth
Bank.  You would report to C. Dowd Ritter, President and Chief Executive
Officer.  You would become a member of our Management Committee, the senior most
management group at AmSouth.  Our three geographic state heads who now report to
Dowd, as well as the three heads of our lines of business who also now report to
Dowd, would report to you.  All other members of the Management Committee who
now report to Dowd would continue to report to him.  Dowd would recommend to the
boards of directors of AmSouth Bancorporation and AmSouth Bank that you be
elected to such boards at the meetings of those boards which immediately precede
your first day of employment.  In addition, Dowd would recommend to those boards
that you be designated as the highest ranking officer after Dowd, in accordance
with the bylaws.

Compensation

     Base Salary.  Your base salary would be $600,000.  You would be eligible
for a merit increase in January 2001, which is the time that merit increases are
normally made for our senior-most managers.
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     Annual Bonus.  You would participate in AmSouth's annual bonus plan for its
senior-most managers, the Executive Incentive Plan.  Each participant in the EIP
has a "base opportunity", expressed as a percentage of base pay, which is
associated with the achievement of goals. Your base bonus opportunity percentage
would be 85%. The actual payout percentage, however, can range from 0% to 200%
of the base bonus opportunity as determined by an evaluation of performance
results against goals. In the case only of your EIP bonus for 2000, payable in
2001, we would guarantee that such bonus would be at least equal to your base
bonus opportunity percentage times your base salary.

     Long Term Incentive Plan.  You would participate in the AmSouth 1996 Long
Term Incentive Plan, a copy of which follows this letter.  You would be granted
options on 400,000 shares of AmSouth Bancorporation common stock, with an
exercise price equal to the fair market value of such stock on the date of
grant.  Such shares would become exercisable in three equal installments on the
first, second and third anniversaries of the date of grant, and would remain
exercisable until the tenth anniversary of the date of grant.  Such options
would be granted under the terms of the LTIP.

     Retirement Plans.  AmSouth has both a qualified defined benefit retirement
plan as well as a non qualified supplemental defined benefit retirement plan,
each of which has a five years of service vesting requirement.  AmSouth also has
both a qualified defined contribution retirement plan, the AmSouth Thrift Plan,
as well as a supplemental defined contribution retirement plan.  Under the
latter two plans, you may defer up to 15% of your base salary per pay period.
Under the terms of the Thrift Plan,  AmSouth will match your pretax deferrals at
a rate of 100%, up to 6% of your gross base salary.

     Executive Severance Agreement.  You would receive an Executive Severance
Agreement which upon a change in control followed within two years by a "good
reason" departure by you or involuntary termination without cause would provide
you with a lump sum cash payment in an amount equal to three times: (a) your
highest annual base salary prior to departure or termination; (b) your highest
recent annual bonus; and (c) the value of an independently determined
competitive annual long term incentive grant.  Your ESA would provide you with a
continuation of all welfare plan benefits for three years, outplacement services
for three years as well as reimbursement for the reasonable cost of relocation
of your primary residence.  Finally, in your ESA or otherwise we would provide
you with written assurance that if, within one year of your first day of
employment by AmSouth, your employment is be terminated other than for cause or
other than due to your death or disability, then you would receive a one-time
lump sum payment equal to the sum of (x) your base bonus opportunity times your
base salary (but you would not receive a bonus under the EIP) plus (y) one times
your base salary.  In addition, AmSouth would pay the reasonable cost of
relocating your primary residence should you decide to leave the Birmingham area
in such circumstances.  Finally, we would also agree that in such circumstances
one-third of the stock options granted to you as described above would vest as
of your last day of employment.
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     Other Benefits.  In addition to the foregoing, you would be eligible for
the other AmSouth benefit plans and perquisite programs which are available for
the senior executives of the company, including the following:

 .  Medical, dental and other health and welfare benefits under AmSouth's general
   health and welfare benefit plans.
 .  Full relocation benefits including home purchase and one-time $125,000
   relocation bonus.
 .  Opportunity to defer payment of EIP bonuses.
 .  Financial planning services at AmSouth expense, through AYCO Companies, LLP.
 .  Reimbursement for country club and Summit Club (private dining club in
   AmSouth-Harbert Plaza) initiation fees and monthly dues.
 .  Home security system.

                                     *****

     Tom, we believe that the above is both a professionally and financially
rewarding opportunity for you.  We would very much like to become your colleague
and have you as a senior member of the AmSouth management team.


                                           Very truly yours,


                                           /s/ David B. Edmonds


cc:  C. Dowd Ritter
     Stephen A. Yoder
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                              [AMSOUTH LETTERHEAD]
                                                               February 15, 2000
Thomas E. Hoaglin
Vice Chairman
AmSouth Bancorporation
1901 Sixth Avenue North
Birmingham, Alabama  35202

     Re:  AmSouth Bancorporation ("AmSouth") Truncated Stock Options

Dear Tom:

Our letter of December 13, 1999 (the "Offer Letter") provided that you would
receive options on 400,000 shares of AmSouth common stock, which options would
be exercisable over a ten year period.  AmSouth has now finalized the terms of a
new type of stock option (a "Truncated Option") which could require an exercise
period substantially shorter than 10 years.  AmSouth intends to grant Truncated
Options to certain senior executives in the first quarter of this year.

You have requested, and AmSouth agrees, that you should receive the same type of
options as other AmSouth senior executives. However, a Truncated Option has a
somewhat lower value than the type of option described in the Offer Letter
because the Truncated Options could require a much shorter exercise period.
In order to bring the value of your Truncated Options into parity with the
options promised you in the Offer Letter, AmSouth has agreed to increase the
number of your Truncated Options as described below.

AmSouth will grant to you in the first quarter of this year Truncated Options on
568,338 shares of AmSouth common stock. The Truncated Options will substantially
conform to the attached term sheet. If one-third of your Truncated Options vest
in accordance with the section of the Offer Letter entitled "Executive Severance
Agreement", the exercise period for such Truncated Options will be ten years
from date of grant. The grant of Truncated Options described in this letter
will be in place of the options on 400,000 shares described in the section of
the Offer Letter entitled "Long Term Incentive Plan", which no longer
apply.


                                          Very truly yours,


                                          /s/ David B. Edmonds