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                                                                    EXHIBIT 4.16




                       ASSIGNMENT AND ASSUMPTION AGREEMENT

                                       to

                               GUARANTEE AGREEMENT

                                     between

                         AMERICAN MUTUAL HOLDING COMPANY

                                       and

                           AMERUS LIFE HOLDINGS, INC.












                            Dated September 20, 2000





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                       ASSIGNMENT AND ASSUMPTION AGREEMENT

     This ASSIGNMENT AND ASSUMPTION AGREEMENT ("Agreement"), dated as of
September 20, 2000, is entered into by and between AMERICAN MUTUAL HOLDING
COMPANY, an Iowa mutual insurance holding company ("AMHC") and AMERUS LIFE
HOLDINGS, INC., an Iowa insurance holding company ("AmerUs").

                                   WITNESSETH:

     WHEREAS, AmerUs and Wilmington Trust Company, a banking corporation duly
organized and existing under the laws of Delaware, as trustee (the "Property
Trustee" or "Guarantee Trustee"), entered into a Trust Agreement, dated as of
October 4, 1996 (the "Original Trust Agreement"), to establish a business trust
pursuant to the Delaware Business Trust Act;

     WHEREAS, AmerUs, the Property Trustee, the Administrative Trustees named
therein, and several Holders as defined therein entered into an Amended and
Restated Trust Agreement (the "Trust Agreement"), dated as of February 3, 1997,
to provide for, among other provisions, the issuance and sale of the Capital
Securities by the Trust;

     WHEREAS, AmerUs and the Guarantee Trustee, for the benefit of the Holders
from time to time of the Capital Securities, executed and delivered a Guarantee
Agreement, dated as of February 3, 1997 (the "Guarantee Agreement"), whereby
AmerUs irrevocably and unconditionally agreed, to the extent set forth in the
Guarantee Agreement, to pay to the Holders the Guarantee Payments and to make
certain other payments on the terms and conditions set forth in the Guarantee
Agreement;

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

     WHEREAS, AMHC desires to assume AmerUs' obligations under the Guarantee
Agreement;

     WHEREAS, this Agreement is being executed pursuant to Section 8.01 of the
Guarantee Agreement;

     WHEREAS, as required by Section 8.01 of the Guarantee Agreement, the Merger
is permitted under Article Eight of the Indenture;


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     NOW, THEREFORE, the parties agree as follows:

SECTION 1.   Assignment.  Upon the execution of this Agreement by the parties
             hereto, AmerUs does hereby assign and transfer all of its
             obligations under the Guarantee Agreement to AMHC, as its
             successor.

SECTION 2.   Assumption. Upon the execution of this Agreement by the
             parties hereto, AMHC does hereby absolutely and irrevocably
             accept the foregoing assignment and hereby assumes to be
             solely responsible for and to perform, as successor, AmerUs'
             obligations under the Guarantee Agreement.

SECTION 3.   Definitions. For all purposes of this Agreement, except as
             otherwise herein expressly provided, the definitions, terms
             and expressions used herein shall have the same meanings as
             corresponding definitions, terms and expressions used in the
             Guarantee Agreement.

SECTION 4.   Effectiveness.  This 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 5.   Binding Effect; Assigns.  This Agreement shall be binding upon,
             and shall enure to the benefit of, the parties thereto and their
             respective successors and assigns.

SECTION 6.   Counterparts.  This 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 7.   Governing Law.  This 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
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



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                                            AMERUS LIFE HOLDINGS, INC.


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