Exhibit 10.1

                     THIRD AMENDMENT TO THE CREDIT AGREEMENT

      THIRD AMENDMENT TO THE CREDIT AGREEMENT (the "Third Amendment"), dated as
of April 12, 2002, among TRENWICK AMERICA CORPORATION, a Delaware corporation
(the "Borrower"), Trenwick Holdings LIMITED., a company organized under the laws
of the United Kingdom (the "Account Party"), the lending institutions from time
to time party to the Credit Agreement referred to below (each a "Bank" and,
collectively, the "Banks"), WACHOVIA BANK, NATIONAL ASSOCIATION (f/k/a 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"). Unless otherwise defined herein, capitalized terms used
herein and defined in the Credit Agreement referred to below are used herein as
so defined.

                              WITNESSETH:

      WHEREAS, the Borrower, the Account Party, the Banks, the Syndication
Agent, the Documentation Agent and 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, the Trenwick Group Ltd., a company organized under the laws of
Bermuda ("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 Credit Agreement as provided herein;

      NOW, THEREFORE, it is agreed;

A.    Amendments

      1. Section 3.01 of the Credit Agreement is hereby amended by inserting the
following new clauses (g) and (h) immediately following clause (f) thereof:



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            "(g) On each Additional Fee Date, if the Borrower has not (i)
      reduced and/or (ii) collateralized with cash, cash equivalents and/or
      marketable securities (subject to the terms set forth on Schedule II
      hereto) in a manner reasonably satisfactory to the Administrative Agent,
      the aggregate Stated Amount of all outstanding Letters of Credit by the
      L/C Exposure Reduction Amount required for such Additional Fee Date, the
      Borrower shall pay a fee to each L/C Bank in an amount equal to 0.50% of
      the L/C Exposure of such L/C Bank as of such Additional Fee Date.

            (h) On each Additional Fee Date, if the Borrower has not reduced the
      aggregate Principal Amount of Term Loans outstanding by the Term Loan
      Reduction Amount required for such Additional Fee Date, the Borrower shall
      pay a fee in amount equal to 0.50% of the aggregate Principal Amount of
      Term Loans outstanding as of such Additional Fee Date to each Bank on a
      pro rata basis."

      2. Section 4.02(i)(b) of the Credit Agreement is hereby amended by (i)
inserting the text "(including, without limitation, issuances of preferred stock
of Holdings pursuant to the terms of the Cat E Put Securities)" immediately
following the text "the sale or issuance of equity" appearing in said Section,
(ii) deleting the comma appearing at the end of clause (ii) of the second
parenthetical of said Section and inserting the word "and" in lieu thereof and
(iii) deleting the text "issuances of preferred stock of Holdings pursuant to
the terms of the Cat E Put Securities and (iv)" appearing in the second
parenthetical of said Section.

      3. Section 4.02(i)(c) of the Credit Agreement is hereby amended by (i)
deleting the reference "(A)" appearing in the proviso in said Section, (ii)
deleting the text ", and" appearing at the end of subclause (A) of the proviso
thereof and (iii) deleting subclause (B) of the proviso thereof in its entirety.

      4. Section 9.03 of the Credit Agreement is hereby amended by (i) deleting
the word "or" immediately following the first parenthetical clause therein and
(ii) inserting the following new clause (c) immediately following clause (b)
thereof:

      "or (c) the Pledge Agreement shall cease to be in full force and effect,
      or shall cease to give the Collateral Agent for the benefit of the Secured
      Creditors the Liens, rights, powers and privileges purported to be created
      thereby (including, without limitation, a perfected security interest in,
      and Lien on, any of the Collateral in favor of the Collateral Agent,
      superior to and prior to the rights of all third Persons (except as
      permitted by Section 4.03 of the Holdings Guaranty) and subject to no
      other Liens (except as permitted by Section 4.03 of the Holdings
      Guaranty), or the default in the due performance or observance of any
      term, covenant or agreement contained in the Pledge Agreement and such
      default shall continue beyond the period of grace, if any, specifically
      applicable thereto pursuant to the terms of such Pledge Agreement, or if
      no period of grace is specifically applicable thereto, such default shall
      continue unremedied for a period of 30 days"

      5. The definition of the term "Applicable Margin" contained in Schedule I
to the Credit Agreement is hereby amended to read in its entirety as follows:

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            "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                  3.50%                   2.25%
            Category F Period                  4.25%                   3.00%

      ; provided that, solely for the purpose of the Term Loans, each 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%."


      6. The definition of the term "Consolidated Net Worth" contained in
Schedule I the Credit Agreement is hereby amended to read in its entirety as
follows:

            "Consolidated Net Worth" shall mean, with respect to any Person, the
      Net Worth of such Person and its Subsidiaries determined on a consolidated
      basis in accordance with GAAP after appropriate deduction for any minority
      interests in Subsidiaries (but, for purposes of determining compliance
      with Sections 4.12 and 4.16 of the Holdings Guaranty, without any
      deduction for any minority interest in LaSalle Re Holdings represented by
      the LaSalle Preferred Stock).

      7. The definition of the term "Credit Documents" contained in Schedule I
to the Credit Agreement is hereby amended to read in its entirety as follows:

            "Credit Documents" shall mean the Credit Agreement, the Holdings
      Guaranty, the Notes, the Subsidiary Guaranty and the Pledge Agreement.

      8. The definition of the term "Holdings Cash Flow" contained in Schedule I
to the Credit Agreement 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


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      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 (excluding up to $75 million in cash
      paid to Lloyd's pursuant to a cash call related to the close of the 1999
      year of accounts with Lloyd's), (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."

      9. The definition of "Quarterly Compliance Date" contained in Schedule I
to the Credit Agreement is hereby amended to read in its entirety as follows:

            "Quarterly Compliance Date" shall mean, for any fiscal quarter, the
      earlier of (i) 45 days after the end of such fiscal quarter and (ii) the
      date on which Holdings delivers to each Bank the compliance certificate
      for such fiscal quarter in accordance with Section 3.01(d) of the Holdings
      Guaranty.

      10. Schedule I to the Credit Agreement is hereby amended by inserting the
following new defined terms in the appropriate alphabetical order:

            "Additional Fee Date" shall mean, each of, September 30, 2002, June
      30, 2003 and June 30, 2004."

            "Collateral" shall have the meaning assigned that term in the Pledge
      Agreement.

            "Collateral Agent" shall mean JPMorgan Chase Bank, as successor to
      The Chase Manhattan Bank, in its capacity as Collateral Agent for the
      Banks under the Credit Documents, and shall include any successor to the
      Collateral Agent.

            "L/C Exposure Reduction Amount" shall mean, for each Additional Fee
      Date, a reduction in the aggregate Stated Amount of all outstanding
      Letters of Credit as of the Third Amendment Effective Date by an amount
      equal to the product of the percentage set forth opposite such Additional
      Fee Date and the aggregate Stated Amount of all outstanding Letters of
      Credit as of the Third Amendment Effective Date:

       Additional Fee Date                                         Percentage
       -------------------                                         ----------
       September 30, 2002                                              40%
         June 30, 2003                                                 60%
         June 30, 2004                                                 80%


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            "Pledge Agreement" means the Pledge Agreement to be executed and
      delivered by Holdings and LaSalle Re Holdings, as the same may be amended,
      supplemented or otherwise modified from time to time.

            "Second Amendment Effective Date" shall mean the date the Second
      Amendment to the Credit Agreement and the Second Amendment to the Holdings
      Guaranty became effective in accordance with their terms.

            "Second Amendment to the Credit Agreement" shall mean the Second
      Amendment to the Credit Agreement, dated as of November 5, 2001.

            "Second Amendment to the Holdings Guaranty" shall mean the Second
      Amendment to the Holdings Guaranty, dated as of November 5, 2001.

            "Secured Creditors" shall have the meaning assigned that term in the
      Pledge Agreement.

            "Term Loan Reduction Amount" shall mean, for each Additional Fee
      Date, a reduction in the aggregate Principal Amount of Term Loans
      outstanding on the Third Amendment Effective Date by an amount equal to
      the product of the percentage set forth opposite such Additional Fee Date
      and the aggregate Principal Amount of Term Loans outstanding as of Third
      Amendment Effective Date:

      Additional Fee Date                                         Percentage
      -------------------                                         ----------
       September 30, 2002                                            40%
         June 30, 2003                                               60%
         June 30, 2004                                               80%

            "Third Amendment Effective Date" shall mean the date the Third
      Amendment to the Credit Agreement and the Third Amendment to the Holdings
      Guaranty became effective in accordance with their terms.

            "Third Amendment to the Credit Agreement" shall mean the Third
      Amendment to this Agreement, dated as of April 12, 2002.

            "Third Amendment to the Holdings Guaranty" shall mean the Third
      Amendment to the Holdings Guaranty, dated as of April 12, 2002.

C. Miscellaneous Provisions

      1. In order to induce the Banks to enter into this Third Amendment, each
of the Borrower and the Account Party hereby represent and warrant on behalf of
themselves and their respective Subsidiaries that (i) the representations and
warranties of contained in Section 2 of the Holdings Guaranty are true and
correct in all material


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respects on and as of the Third 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 Third Amendment Effective Date, in each case
after giving effect to this Third Amendment.

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

      3. THIS THIRD 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 Third Amendment shall become effective on the date (the "Third
Amendment Effective Date") when each of the following conditions have been
satisfied:

            (i) the Borrower, the Account Party 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) Holdings and the Required Banks have consented to the Third
      Amendment to the Holdings Guaranty dated as of April 12, 2002 (the
      "Holdings Guaranty Amendment").

      5. The Borrower hereby agrees to pay each Bank which delivers an executed
copy of this Third Amendment and the Holdings Guaranty Amendment (by hard copy
or facsimile) to the Administrative Agent a fee (the "Amendment Fee") in an
amount equal to 0.50% of the outstanding principal amount of Term Loans and L/C
Commitment of such Bank, which Amendment Fee shall be due and payable on the
fifth Business Day following the date on which the Required Banks shall have
executed and delivered this Third Amendment and the Holdings Guaranty Amendment.

      6. From and after the Third Amendment Effective Date, all references in
the Credit Agreement and in the other Credit Documents shall be deemed to be
referenced to the Credit Agreement as modified hereby.

                                      * * *


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

                                       TRENWICK AMERICA CORPORATION


                                       By:
                                          -------------------------------------
                                          Name:
                                          Title:

                                       TRENWICK HOLDINGS LIMITED


                                       By:
                                          -------------------------------------
                                          Name:
                                          Title:


<PAGE>


                                       [NAME OF LENDER]


                                       By:
                                           ------------------------------------
                                           Name:
                                           Title:


         [Signature Page to the Third Amendment to the Credit Agreement]


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                                                                     SCHEDULE II

                TERMS FOR COLLATERALIZATION OF LETTERS OF CREDIT

Cash, MMA's, CD's and TD's  - 100%

US T-Bills (<1year) - 95%
US T-Notes (<2 years) - 90%
T Notes, Bonds (>2 years) 80% of market value

US Agencies:
< 2 years maturity - 95%
2 yrs to 10 yrs maturity - 90%
> 10 years - 85%

US Muni bonds:
Aaa/AAA - 90%
Baa/BBB or better - 80%