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                                                                   EXHIBIT 4.22



                                FIRST SUPPLEMENT

                                       to

                                PLEDGE AGREEMENT

                                      among

                        AMERICAN MUTUAL HOLDING COMPANY,

                              GOLDMAN, SACHS & CO.,
                             as Call Option Holder,

                            THE CHASE MANHATTAN BANK,
                               as Collateral Agent

                                       and

                           FIRST UNION NATIONAL BANK,
                                  as Unit Agent









                            Dated September 20, 2000




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                          FIRST SUPPLEMENTAL AGREEMENT

     This First Supplemental Agreement (this "First Supplemental Agreement"),
dated as of September 20, 2000, is among AMERICAN MUTUAL HOLDING COMPANY, an
Iowa mutual insurance holding company ("AMHC"), as successor to AMERUS LIFE
HOLDINGS, INC., an Iowa insurance holding company (the "Company"), GOLDMAN,
SACHS & CO., as Call Option Holder (the "Call Option Holder"), THE CHASE
MANHATTAN BANK, as Collateral Agent (the "Collateral Agent"), and FIRST UNION
NATIONAL BANK, as Unit Agent (the "Unit Agent").

     WHEREAS, the Company and the Unit Agent entered into a Master Unit
Agreement, dated as of July 27, 1998 (the "Master Unit Agreement"), in which the
obligations of the Company under the Units are provided;

     WHEREAS, the Company, Call Option Holder, Collateral Agent and Unit Agent
entered into a Pledge Agreement, dated as of July 27, 1998 (the "Pledge
Agreement"), as provided by the Master Unit Agreement, whereby the QUIPS",
Junior Subordinated Debentures or Treasury Securities that from time to time
underlie the Units are pledged to the Collateral Agent to secure the obligations
of the Holders of Units under the Purchase Contracts and Call Options that
underlie such Units;

     WHEREAS, AMHC has executed a Plan of Conversion, dated as of December 17,
1999, pursuant to which AMHC will convert from a mutual insurance holding
company into a stock holding company;

     WHEREAS, the Company and AMHC have entered into an Agreement and Plan of
Merger, dated December 17, 1999, pursuant to which the Company will merge with
and into AMHC, with AMHC continuing as the surviving company (the "Merger"); and

     WHEREAS, AMHC wishes to assume the obligations of the Company under the
Pledge Agreement, pursuant to the requirements of Article Nine of the Master
Unit Agreement, as authorized by Article Eight of the Master Unit Agreement and
without the consent of the Holders.

     NOW THEREFORE, in consideration of the foregoing, the parties agree as
follows:

Section 1.      Capitalized terms not otherwise defined herein shall have
                the meanings set forth in the Master Unit Agreement and the
                Pledge Agreement.

Section 2.      AMHC hereby agrees to assume the obligations of the
                Company, as its successor, under the Pledge Agreement and to
                be bound by the provisions of such agreement.



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Section 3.      This First Supplemental Agreement shall become effective as
                of the Effective Time (as defined in the Agreement and Plan of
                Merger referred to above) of the Merger.

Section 4.      This First Supplemental Agreement may be executed in two or
                more counterparts, each of which will be deemed to be an
                original, but all of which together will constitute one and
                the same agreement.

Section 5.      This First Supplemental Agreement will be governed by and
                interpreted in accordance with the internal laws of the State
                of New York, without giving effect to principles of conflicts
                of laws.

                IN WITNESS WHEREOF, the parties hereto have executed and
delivered this Supplemental Agreement as of the date set forth above.


                                    AMERICAN MUTUAL HOLDING COMPANY


                                    By:  /s/ Roger K. Brooks
                                         --------------------------------------
                                         Name:  Roger K. Brooks
                                         Title: Chairman, President and
                                                Chief Executive Officer


                                    GOLDMAN, SACHS & CO.,
                                    as Call Option Holder


                                    By:  /s/ Paul S. Efron
                                         --------------------------------------
                                         Name:  Paul S. Efron
                                         Title: Managing Director



                                    THE CHASE MANHATTAN BANK,
                                    as Collateral Agent and Securities
                                    Intermediary


                                    By:  /s/ L.O. Brien
                                         --------------------------------------
                                         Name:  L.O. Brien
                                         Title: Vice President

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                                    FIRST UNION NATIONAL BANK,
                                    as Unit Agent and as attorney-in-fact of
                                    the Holders from time to time of the Units


                                    By:  /s/ Shawn K. Bednasek
                                         --------------------------------------
                                    Name:  Shawn K. Bednasek
                                    Title:    Vice President



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