Exhibit 4.3

                              TRUST AGREEMENT OF
                                 FBS CAPITAL I


          This TRUST AGREEMENT of FBS CAPITAL I (the "Trust"), dated as of
October 31, 1996, among (i) First Bank System, Inc.,  a Delaware corporation
(the "Depositor"), (ii) Wilmington Trust Company, a Delaware banking
corporation, not in its individual capacity but solely as trustee of the Trust,
and (iii), Lee R. Mitau, Susan E. Lester and David J. Parrin, each an individual
employed by the Depositor, not in their individual capacities but solely as
administrative trustees of the Trust (each of such trustees in (ii) and (iii) a
"Trustee" and collectively, the "Trustees").  The Depositor and the Trustees
hereby agree as follows:

          1.   The Trust created hereby shall be known as "FBS Capital I", 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 Trustees the sum of $10.  The Trustees hereby acknowledge receipt of such
amount in trust from the Depositor, which amount shall constitute the initial
trust estate.  The Trustees hereby declare that they will hold the trust estate
in trust 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. (S) 3801 et seq. (the "Business Trust Act"), and
that this document constitutes the governing instrument of the Trust.  The
Trustees hereby are authorized and directed to execute and file a certificate of
trust with the Secretary of State of the State of Delaware in accordance with
the provisions of the Business Trust Act.

 
          3.   The Depositor and the Trustees will enter into an Amended and
Restated Trust Agreement, satisfactory to each such party and substantially in
the form to be included as an exhibit to the 1933 Act Registration Statement
referred to below, to provide for the contemplated operation of the Trust
created hereby and the issuance of the Preferred Securities and Common
Securities referred to therein.  Prior to the execution and delivery of such
Amended and Restated Trust Agreement, the Trustees shall not have any duty or
obligation hereunder or with respect of the trust estate, except as otherwise
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.

          4.   The Trustees hereby authorize and direct the Depositor (i) to
file with the Securities and Exchange Commission (the "Commission") and execute,
in each case on behalf of the Trust, (a) a Registration Statement on Form S-3
(the "1933 Act Registration Statement"), including any pre-effective or post-
effective amendments to the 1933 Act Registration Statement, relating to the
registration under the Securities Act of 1933, as amended, of the Preferred
Securities of the Trust and certain other securities and (b) a Registration
Statement on Form 8-A (the "1934 Act Registration Statement") (including all
pre-effective and post-effective amendments thereto) relating to the
registration of the Preferred Securities of the Trust under Section 12(b) of the
Securities Exchange Act of 1934, as amended; (ii) to file with the New York
Stock Exchange (the "Exchange") and execute on behalf of the Trust a listing
application and all other applications, statements, certificates, 

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agreements and other instruments as shall be necessary or desirable to cause the
Preferred Securities to be listed on the Exchange and (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 as shall be necessary or desirable to register the Preferred
Securities under the securities or blue sky laws of such jurisdictions as the
Depositor, on behalf of the Trust, may deem necessary or desirable. In the event
that any filing referred to above is required by the rules and regulations of
the Commission, the Exchange or state securities or blue sky laws, to be
executed on behalf of the Trust by one or more of the Trustees, each of the
Trustees, in its or his capacity as Trustee of the Trust, is hereby authorized
and, to the extent so required, directed to join in any such filing and to
execute on behalf of the Trust any and all of the foregoing, it being understood
that Wilmington Trust Company in its capacity as Trustee of the Trust, shall not
be required to join in any such filing or execute on behalf of the Trust any
such document unless required by the rules and regulations of the Commission,
the Exchange or state securities or blue sky laws. In connection with the
filings referred to above, the Depositor and Lee R. Mitau, Susan E. Lester and
David J. Parrin, each an administrative trustee, solely in their capacities as
Trustees of the Trust, hereby constitutes and appoints Lee R. Mitau, Susan E.
Lester and David J. Parrin, each of them, as its or his or her true and lawful
attorneys-in-fact and agents, with full power of substitution and
resubstitution, for the Depositor or such Trustee or in the Depositor's or such
Trustee's name, place and stead, in any and all capacities, to sign 

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any and all amendments (including post-effective amendments) to any such filings
(including the 1933 Act Registration Statement and the 1934 Act Registration
Statement) and to file the same, with all exhibits thereto and other documents
in connection therewith, with the Commission, the Exchange and administrators of
state securities or blue sky laws, granting unto said attorneys-in-fact and
agents full power and authority to do and perform each and every act and thing
requisite and necessary to be done in connection therewith, as fully to all
intents and purposes as the Depositor or such Trustee might or could do in
person, thereby ratifying and confirming all that said attorneys-in-fact and
agents or any of them, or their respective substitute or substitutes, shall do
or cause to be done by virtue thereof.

          5.   This Trust Agreement may be executed in one or more counterparts.

          6.   The number of Trustees initially shall be four (4) 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, however, that to the extent required by the
Business Trust Act, one Trustee shall be either a natural person who is a
resident of the State of Delaware, or, if not a natural person, an entity which
has its principal place of business in the State of Delaware and otherwise meets
the requirements of applicable Delaware law.  Subject to the foregoing, the
Depositor is entitled to appoint or remove without cause any Trustee at any
time.  The Trustees may resign upon thirty days prior written notice to
Depositor.

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          7.   This Trust Agreement shall be governed by, and construed in
accordance with, the laws of the State of Delaware (without regard to conflict
of laws principles).

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

                                              /s/ David J. Parrin
FIRST BANK SYSTEM, INC.,                     -----------------------------------
     as Depositor                            DAVID J. PARRIN, not in his
                                             individual capacity but solely as
                                               Administrative Trustee
By: /s/ Lee R. Mitau
   ---------------------------------------
Name:  Lee R. Mitau                           /s/ Susan E. Lester
Title: Executive Vice President,             -----------------------------------
       General Counsel and Secretary         SUSAN E. LESTER, not in her
                                             individual capacity but solely as
                                               Administrative Trustee

                                               /s/ Lee R. Mitau
WILMINGTON TRUST COMPANY,                    -----------------------------------
not in its individual capacity but solely    LEE R. MITAU, not in his
as Trustee                                   individual capacity but solely as
                                               Administrative Trustee

By: /s/ Norma P. Closs
   ---------------------------------------
Name:  Norma S. Closs
Title: Vice President

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