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                                                                    Exhibit 99.1


[WHITE MOUNTAINS LOGO]                                             PRESS RELEASE

                                                              CONTACT: David Foy
                                                             Tel: (203) 453-1681


             WHITE MOUNTAINS, BERKSHIRE HATHAWAY AND OTHER INVESTORS
                     TO ACQUIRE SAFECO LIFE AND INVESTMENTS

HAMILTON, Bermuda, March 15, 2004 - White Mountains Insurance Group, Ltd. (NYSE:
WTM) announced today that it and Berkshire Hathaway Inc. are leading an investor
group that will acquire the life and investments business of Safeco Corporation
for $1.35 billion, subject to adjustment based on June 30, 2004 adjusted
statutory book value.

Safeco Life and Investments, with headquarters in Redmond, Washington, focuses
mainly on group insurance, individual life insurance, structured settlements,
retirement services and mutual funds. As of December 31, 2003, the business had
approximately $22.5 billion of total assets and $2.57 billion in GAAP book value
($1.74 billion excluding FAS 115). President Randy Talbot and his management
team will continue to run the business following the acquisition.

A newly formed acquisition company will be capitalized with equity of
approximately $1.0 billion, with White Mountains and Berkshire Hathaway each
investing $200 million. The acquisition company also has secured committed bank
financing of up to $350 million. White Mountains and Berkshire Hathaway are
receiving warrants to purchase additional common shares of the company. On a
fully converted basis, White Mountains and Berkshire Hathaway will each own
approximately 24% of the company.

Investors in the group include, among others, Caxton Associates, L.L.C.,
Highfields Capital Management, Och-Ziff Capital Management, Vestar Capital
Partners, DLJ Growth Capital Partners, L.P., CAI Capital Partners and Company
III, L.P., Fairholme Capital Management and Prospector Partners.

White Mountains expects the transaction to close during the third quarter of
2004. The transaction is subject to regulatory approvals and other customary
closing conditions.

                             ADDITIONAL INFORMATION

White Mountains is a Bermuda-domiciled financial services holding company traded
on the New York Stock Exchange and the Bermuda Stock Exchange under the symbol
WTM. Additional financial information and other items of interest are available
at the Company's web site located at WWW.WHITEMOUNTAINS.COM.

- --------------------------------------------------------------------------------
CORPORATE HEADQUARTERS:                 EXECUTIVE OFFICES:
- ----------------------                  -----------------
WHITE MOUNTAINS INSURANCE GROUP, LTD.   WHITE MOUNTAINS INSURANCE GROUP, LTD.
12 CHURCH STREET, SUITE 322             80 SOUTH MAIN STREET, HANOVER, NH 03755
HAMILTON, HM 11   BERMUDA               PH: 603-640-2200 FAX: 603-643-4592
PH: 441-296-6011  FAX: 441-296-9904     WWW.WHITEMOUNTAINS.COM




SAFE HARBOR STATEMENT UNDER THE PRIVATE SECURITIES LITIGATION REFORM ACT OF 1995

       THIS PRESS RELEASE MAY CONTAIN "FORWARD-LOOKING STATEMENTS" WITHIN THE
MEANING OF SECTION 27A OF THE SECURITIES ACT OF 1933 AND SECTION 21E OF THE
SECURITIES EXCHANGE ACT OF 1934. ALL STATEMENTS, OTHER THAN STATEMENTS OF
HISTORICAL FACTS, INCLUDED OR REFERENCED IN THIS RELEASE WHICH ADDRESS
ACTIVITIES, EVENTS OR DEVELOPMENTS WHICH WE EXPECT OR ANTICIPATE WILL OR MAY
OCCUR IN THE FUTURE ARE FORWARD-LOOKING STATEMENTS. THE WORDS "BELIEVE,"
"INTEND," "EXPECT," "ANTICIPATE," "PROJECT," "ESTIMATE," "PREDICT" AND SIMILAR
EXPRESSIONS ARE ALSO INTENDED TO IDENTIFY FORWARD-LOOKING STATEMENTS. THESE
FORWARD-LOOKING STATEMENTS INCLUDE, AMONG OTHERS, STATEMENTS WITH RESPECT TO
WHITE MOUNTAINS':

       X    GROWTH IN BOOK VALUE PER SHARE OR RETURN ON EQUITY;

       X    BUSINESS STRATEGY;

       X    FINANCIAL AND OPERATING TARGETS OR PLANS;

       X    INCURRED LOSSES AND THE ADEQUACY OF ITS LOSS AND LOSS ADJUSTMENT
            EXPENSE RESERVES;

       X    PROJECTIONS OF REVENUES, INCOME (OR LOSS), EARNINGS (OR LOSS) PER
            SHARE, DIVIDENDS, MARKET SHARE OR OTHER FINANCIAL FORECASTS;

       X    EXPANSION AND GROWTH OF ITS BUSINESS AND OPERATIONS; AND

       X    FUTURE CAPITAL EXPENDITURES.

       THESE STATEMENTS ARE BASED ON CERTAIN ASSUMPTIONS AND ANALYSES MADE BY
WHITE MOUNTAINS IN LIGHT OF ITS EXPERIENCE AND PERCEPTION OF HISTORICAL TRENDS,
CURRENT CONDITIONS AND EXPECTED FUTURE DEVELOPMENTS, AS WELL AS OTHER FACTORS
BELIEVED TO BE APPROPRIATE IN THE CIRCUMSTANCES. HOWEVER, WHETHER ACTUAL RESULTS
AND DEVELOPMENTS WILL CONFORM WITH ITS EXPECTATIONS AND PREDICTIONS IS SUBJECT
TO A NUMBER OF RISKS AND UNCERTAINTIES THAT COULD CAUSE ACTUAL RESULTS TO DIFFER
MATERIALLY FROM EXPECTATIONS, INCLUDING:


       X    THE FAILURE OF THE ACQUISITION TO BE COMPLETED OR, IF THE
            ACQUISITION IS COMPLETED, ITS FAILURE TO ENHANCE SHAREHOLDER VALUE;

       X    CLAIMS ARISING FROM CATASTROPHIC EVENTS, SUCH AS HURRICANES,
            EARTHQUAKES, FLOODS OR TERRORIST ATTACKS;

       X    THE CONTINUED AVAILABILITY OF CAPITAL AND FINANCING;

       X    GENERAL ECONOMIC, MARKET OR BUSINESS CONDITIONS;

       X    BUSINESS OPPORTUNITIES (OR LACK THEREOF) THAT MAY BE PRESENTED TO IT
            AND PURSUED;

       X    COMPETITIVE FORCES, INCLUDING THE CONDUCT OF OTHER INSURERS AND
            REINSURERS;

       X    CHANGES IN DOMESTIC OR FOREIGN LAWS OR REGULATIONS APPLICABLE TO
            WHITE MOUNTAINS, ITS COMPETITORS OR ITS CLIENTS;

       X    AN ECONOMIC DOWNTURN OR OTHER ECONOMIC CONDITIONS ADVERSELY
            AFFECTING ITS FINANCIAL POSITION;

       X    LOSS RESERVES ESTABLISHED SUBSEQUENTLY PROVING TO HAVE BEEN
            INADEQUATE; AND

       X    OTHER FACTORS, MOST OF WHICH ARE BEYOND WHITE MOUNTAINS' CONTROL.

       CONSEQUENTLY, ALL OF THE FORWARD-LOOKING STATEMENTS MADE IN THIS PRESS
RELEASE ARE QUALIFIED BY THESE CAUTIONARY STATEMENTS, AND THERE CAN BE NO
ASSURANCE THAT THE ACTUAL RESULTS OR DEVELOPMENTS ANTICIPATED BY WHITE MOUNTAINS
WILL BE REALIZED OR, EVEN IF SUBSTANTIALLY REALIZED, THAT THEY WILL HAVE THE
EXPECTED CONSEQUENCES TO, OR EFFECTS ON, WHITE MOUNTAINS OR ITS BUSINESS OR
OPERATIONS. WHITE MOUNTAINS ASSUMES NO OBLIGATION TO UPDATE PUBLICLY ANY SUCH
FORWARD-LOOKING STATEMENTS, WHETHER AS A RESULT OF NEW INFORMATION, FUTURE
EVENTS OR OTHERWISE.