Exhibit 10.4


                    SECOND AMENDMENT TO THE HOLDINGS GUARANTY

     SECOND AMENDMENT TO THE HOLDINGS  GUARANTY (the  "Amendment"),  dated as of
November 5, 2001, among TRENWICK GROUP LTD., a company  organized under the laws
of Bermuda  ("Holdings") and the Banks party to the Credit Agreement referred to
below.  Unless  otherwise  defined  herein,  capitalized  terms used  herein and
defined  in the  Holdings  Guaranty  referred  to below  are used  herein  as so
defined.

                              W I T N E S S E T H :
                              - - - - - - - - - -

     WHEREAS,   Trenwick  America  Corporation,   a  Delaware  corporation  (the
"Borrower"),  Trenwick  Holdings Ltd., a company organized under the laws of the
United Kingdom (the "Account Party"), the lending institutions from time to time
party  thereto  (each a "Bank"  and,  collectively,  the  "Banks"),  First Union
National Bank, as Syndication  Agent (the "Syndication  Agent"),  Fleet National
Bank, as Documentation  Agent (the  "Documentation  Agent"),  and JPMorgan Chase
Bank  (f/k/a  The  Chase   Manhattan   Bank),  as   Administrative   Agent  (the
"Administrative  Agent"), are party to a Credit Agreement,  dated as of November
24, 1999 and amended and restated as of September 27, 2000 (as the same has been
amended,  modified or supplemented to, but not including,  the date hereof,  the
"Credit Agreement");

     WHEREAS,  Holdings  and the  Administrative  Agent  entered into a Holdings
Guaranty, dated as of September 27, 2000 (as the same has been amended, modified
or supplemented to, but not including, the date hereof, the "Holdings Guaranty")
in order to induce the Banks to make Loans to the Borrower and issue  Letters of
Credit for the  account  of the  Account  Party and  Guaranteed  Creditors  (and
Lending  Affiliates  thereof) to enter into Interest Rate Protection  Agreements
and Other Hedging Agreements with the Borrower and/or the Account Party; and

     WHEREAS,  subject to the terms and conditions set forth below,  the parties
hereto wish to amend the Holdings Guaranty as provided herein;

     NOW, THEREFORE, it is agreed;

A.   Amendments and Consents

     1. Section  4.04(i) of the Holdings  Guaranty is hereby amended by deleting
the amount  "$50,000,000"  appearing  in said Section and  inserting  the amount
"$25,000,000" in lieu thereof.

     2. Section 4.13 of the Holdings  Guaranty is hereby  amended to read in its
entirety as follows:


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          "4.13 Interest  Coverage Ratio.  Holdings will not permit the Interest
     Coverage  Ratio for any Test Period  ending during a period set forth below
     to be less than the ratio set forth opposite such period below:


                        Period                                Ratio
                        ------                                -----
           Fiscal Year ending 12/31/00                      2.50:1.00
           Fiscal Quarter ending 9/30/01                    2.75:1.00
           Fiscal Quarter ending 12/31/01                   1.50:1.00
           Fiscal Quarter ending 3/31/02                    2.00:1.00
           Thereafter                                       2.50:1.00"


     3. Section 4.14 of the Holdings  Guaranty is hereby  amended to read in its
entirety as follows:

          "4.14.  Minimum Risk Based  Capital.  (a) Holdings will not permit the
     Risk Based Capital Ratio for Trenwick America Reinsurance Corporation to be
     less than 325%.

          (b)  Holdings  will not permit the Risk  Based  Capital  Ratio for any
     Regulated  Insurance  Company  which is a Domestic  Subsidiary  (other than
     Trenwick America  Reinsurance  Corporation) to be less than 300%;  provided
     that, during the period from the Amendment  Effective Date through December
     31, 2002 the Risk Based Capital Ratio for Chartwell Insurance Company shall
     not be less than 225%."

     4. Section 4.16 of the Holdings Guaranty is hereby amended by inserting the
following  text  immediately  preceding the period at the end of said Section ";
provided  that  during  the  period  from the  Amendment  Effective  Date to the
Quarterly  Compliance Date,  Holdings will not permit its Consolidated  Tangible
Net Worth at any time to be less than the sum of (i) $425,000,000, plus (ii) 50%
of  Consolidated  Net Income (if positive) from and after October 1, 2001 to the
last day of the most recently ended fiscal quarter.

     5.  The  definition  of the term  "Applicable  Commitment  Fee  Percentage"
contained  in  Schedule  I to the  Holdings  Guaranty  is hereby  amended by (i)
inserting the phrase "Category F Period"  immediately below the phrase "Category
E Period" in the column "Applicable Period" appearing therein and (ii) inserting
the percentage "0.500%"  immediately below the percentage "0.500%" in the column
"Applicable Commitment Fee Percentage" appearing therein.

     6. The  definition  of the term  "Applicable  Credit  Rating"  contained in
Schedule I to the  Holdings  Guaranty  is hereby  amended by  deleting  the text
"BBB-/Baa3" appearing therein and inserting the text "BB+/Ba1" in lieu thereof.


                                      -2-
<PAGE>


     7. The definition of the term "Applicable  Margin"  contained in Schedule I
to the Holdings Guaranty is hereby amended to read in its entirety as follows:

          "Applicable  Margin"  shall mean,  for any day, the rate per annum set
     forth below opposite the Applicable Period then in effect:

                                                  Applicable Margin
                                                  -----------------
          Applicable Period          Eurodollar Loans            Base Rate Loans
          -----------------          ----------------            ---------------

          Category A Period             1.10%                        0.00%
          Category B Period             1.30%                        0.05%
          Category C Period             1.50%                        0.25%
          Category D Period             2.00%                        0.75%
          Category E Period             2.50%                        1.25%
          Category F Period             3.25%                        2.00%

     ; provided that,  solely for the purpose of the Term Loans,  the Applicable
     Margin  shall be increased by the rate per annum set forth below during the
     period set forth opposite such rate per annum:

                              Period                          Percentage
        July 1, 2002 through September 30, 2002                 0.50%
        October 1, 2002 through December 31, 2002               1.00%
        January 1, 2003 through March 31, 2003                  1.50%
        April 1, 2003 and thereafter                            2.00%."


     8. The definition of the term "Applicable  Period"  contained in Schedule I
to the Holdings Guaranty is hereby amended to read in its entirety as follows:

          "Applicable  Period"  shall  mean,  at any time,  the period set forth
     below then in effect:

         Applicable Period                     Criteria
         -----------------                     --------

         Category A Period       The Applicable Credit Rating is A-/A3 or above.

         Category B Period       The Applicable Credit Rating is BBB+/Baa1.

         Category C Period       The Applicable Credit Rating is BBB/Baa2.

         Category D Period       The Applicable Credit Rating is BBB-/Baa3.

         Category E Period       The Applicable Credit Rating is BB+/Ba1


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          Applicable Period                       Criteria
          -----------------                       --------

          Category F Period         None of a  Category  A Period,  a Category B
                                    Period,  a Category  C Period,  a Category D
                                    Period  nor a Category E Period is in effect
                                    at such time.

                  Notwithstanding  anything to the contrary set forth above,  if
         neither Rating Agency rates the unsecured  senior debt of the Borrower,
         then the Applicable Period shall be a Category F Period."

     9. The definition of the term "Holdings Cash Flow"  contained in Schedule I
to the Holdings Guaranty is hereby amended to read in its entirety as follows:

          "Holdings  Cash Flow" shall mean,  for any period,  the sum of (i) for
     each  Specified  Regulated  Insurance  Company,  the  aggregate  amount  of
     ordinary dividends which such Specified  Regulated  Insurance Company could
     pay to its parent  corporation under Legal  Requirements as of the last day
     of such period  (determined  as if (x) such Specified  Regulated  Insurance
     Company had not paid any ordinary dividends during such period and (y) each
     Subsidiary  of  such  Specified  Regulated  Insurance  Company  which  is a
     Regulated  Insurance  Company had paid dividends to its parent  corporation
     during such period in an amount  equal to the maximum  amount of  dividends
     payable by such  Subsidiary  during  such  period  under  applicable  Legal
     Requirements)  plus the  aggregate  amount of any  extraordinary  dividends
     actually paid by such Specified  Regulated  Insurance Company to its parent
     corporation  during  such  period,  (ii)  for  each  Specified  Foreign  or
     Non-Regulated  Company,  (x) the  greater of (A) zero and (B) the EBITDA of
     such Specified Foreign or Non-Regulated  Company for such period, minus (y)
     the  amount  of  capital  contributions  and  intercompany  loans  made  by
     Holdings, the Borrower or any Specified Regulated Insurance Company to such
     Specified  Foreign or  Non-Regulated  Company on or after  October 1, 2001,
     (iii) tax sharing payments made by Regulated  Insurance Companies which are
     Domestic Subsidiaries  directly to Holdings or any Specified  Non-Regulated
     Company  during such period  (less cash taxes paid by Holdings  during such
     period),  and (iv) payments during such period of principal and interest on
     surplus notes issued by Regulated  Insurance  Companies  which are Domestic
     Subsidiaries to Holdings or any Specified Non-Regulated Company."

     10.  The  definition  of the term  "Trust  Preferred  Securities  Purchase"
contained  in Schedule I to the Holdings  Guaranty is hereby  amended to read in
its entirety as follows:

          "Trust Preferred  Securities  Purchase" shall mean the purchase by one
     or more Subsidiaries of Holdings of approximately $23,700,000 of face value
     Trust Preferred Securities for approximately $18,000,000 in cash during the
     fiscal  quarter  ending  December 31, 2000,  and the fiscal  quarter ending
     March 31, 2001.

     11. Schedule I to the Holdings  Guaranty is hereby amended by inserting the
following definition in the appropriate alphabetical order:


                                      -4-
<PAGE>


          "Quarterly Compliance Date" shall mean the earlier of (i) May 15, 2002
     and (ii) the date on which  Holdings  delivers to each Bank the  compliance
     certificate  for the fiscal  quarter  ending March 31, 2002,  in accordance
     with Section 3.01(d) of the Holdings Guaranty."

B.   Miscellaneous Provisions

     1. In order to induce  the Banks to enter  into  this  Amendment,  Holdings
hereby  represents and warrants that (i) the  representations  and warranties of
Holdings contained in the Holdings Guaranty are true and correct in all material
respects on and as of the Amendment  Effective  Date (as defined  below) (except
with respect to any  representations  and warranties limited by their terms to a
specific  date,  which shall be true and correct in all material  respects as of
such  date),  and (ii) there  exists no  Default  or Event of Default  under the
Credit  Agreement on the  Amendment  Effective  Date,  in each case after giving
effect to this Amendment.

     2. This  Amendment  is limited as  specified  and shall not  constitute  an
amendment,  modification,  acceptance  or waiver of any other  provision  of the
Holdings Guaranty or any other Credit Document.

     3. THIS AMENDMENT AND THE RIGHTS AND  OBLIGATIONS OF THE PARTIES  HEREUNDER
SHALL BE  CONSTRUED IN  ACCORDANCE  WITH AND GOVERNED BY THE LAW OF THE STATE OF
NEW YORK.

     4. This  Amendment  shall  become  effective  on the date  (the  "Amendment
Effective  Date") when (i) Holdings  and the Required  Banks shall have signed a
counterpart  hereof (whether the same or different  counterparts) and shall have
delivered  (including by way of telecopier) the same to the Administrative Agent
and (ii) the Borrower,  the Account Party and the Required  Banks have consented
to the Second  Amendment and Waiver to the Credit  Agreement,  dated November 5,
2001.

     5. From and after the  Amendment  Effective  Date,  all  references  in the
Holdings  Guaranty  and in the  other  Credit  Documents  shall be  deemed to be
referenced to the Holdings Guaranty as modified hereby.


                                      * * *


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<PAGE>


     IN WITNESS  WHEREOF,  the undersigned have caused this Amendment to be duly
executed and delivered as of the date first above written.


                                        TRENWICK GROUP LTD.


                                        By:  /s/ Coleman D. Ross
                                           -------------------------------------
                                             Name:  Coleman D. Ross
                                             Title:  Chief Financial Officer




                                               [Bank Signature Pages Omitted]