Exhibit 8.1

                  [Letterhead of Willkie Farr & Gallagher LLP]

July 25, 2005

W. R. Berkley Corporation
W. R. Berkley Capital Trust II
475 Steamboat Road
Greenwich, Connecticut 06830

      RE:   W. R. BERKLEY CORPORATION -- 6.750% TRUST PREFERRED SECURITIES DUE
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Ladies and Gentlemen:

      We have acted as special tax counsel for W. R. Berkley Corporation, a
Delaware corporation (the "Company"), and W. R. Berkley Capital Trust II, a
Delaware statutory trust (the "Trust"), in connection with the proposed issuance
and sale pursuant to the Purchase Agreement, dated July 19, 2005 (the "Purchase
Agreement"), by and among the Company, the Trust, Merrill Lynch, Pierce, Fenner
& Smith Incorporated, Citigroup Global Markets Inc., Morgan Stanley & Co.
Incorporated and UBS Securities LLC, as representatives of the several
underwriters named therein, of 10,000,000 6.750% Trust Originated Preferred
Securities(SM) (liquidation amount $25 per security) of the Trust (the "Trust
Preferred Securities"), which will represent undivided beneficial interests in
the assets of the Trust.

      In furnishing this opinion, we have reviewed the (i) prospectus supplement
dated July 19, 2005 to the Prospectus dated December 23, 2003 (the "Prospectus
Supplement"), filed as part of the registration statement on Form S-3, as
amended (Registration No. 333-109621; declared effective on December 23, 2003),
(ii) Certificate of Trust of W. R. Berkley Capital Trust II, dated March 22,
2001 (the "Certificate") and (iii) form of Amended and Restated Declaration of
Trust of W. R. Berkley Capital Trust II to be entered into by and among the
Company, The Bank of New York, as Property Trustee, The Bank of New York
(Delaware), as Delaware Trustee, the Administrative Trustees named therein, and
the Holders, as defined therein (the "Amended and Restated Declaration of
Trust"). In addition, we have examined such records, documents, certificates or
other instruments as in our judgment are necessary or appropriate to enable us
to render the opinion expressed below. In this examination, we have assumed (i)
the genuineness of all signatures on relevant documents, (ii) the authenticity,
validity and enforceability of all relevant documents, (iii) conformity to
original documents of all documents submitted to us as certified or copies, (iv)
the transactions described in the Prospectus Supplement and the Purchase
Agreement are performed in the manner described therein, (v) full compliance
with the terms of the Amended and Restated Declaration of Trust and (vi) that
the Amended and Restated Declaration of Trust will constitute the entire
agreement among the parties thereto with respect to the subject matter thereof,
and that the Amended and Restated Trust Agreement and Certificate will be in
full force and effect and will not be amended.



W. R. Berkley Corporation
W. R. Berkley Capital Trust II
July 25, 2005
Page 2

      Based on the foregoing, and subject to the limitations, qualifications and
assumptions set forth herein, (i) we are of the opinion that the Trust will be
classified as a grantor trust and not as an association taxable as a corporation
for federal income tax purposes and (ii) we confirm that the statements of law
and legal conclusions set forth under the heading "United States Federal Income
Tax Consequences" in the Prospectus Supplement represent our opinion.

      Our opinion is based on current provisions of the Internal Revenue Code of
1986, as amended, the Treasury Regulations promulgated thereunder, published
pronouncements of the Internal Revenue Service and case law, any of which may be
changed at any time with retroactive effect. Any change in applicable laws or
facts, or any change or inaccuracy in the statements, facts or assumptions on
which we have relied, may affect the validity of the opinion set forth above. We
assume no responsibility to inform you of any such change or inaccuracy that may
occur or come to our attention. No opinion is expressed on any matter other than
that specifically covered by this opinion.

      This opinion is limited to the federal income taxation laws of the United
States and does not cover matters arising under or relating to the laws of any
other jurisdiction, including, without limitation, the laws of any other
non-U.S. jurisdiction or the laws of any State of the United States, the
District of Columbia or any political subdivision of any of these.

      We consent to the filing of this opinion as an exhibit to the Company's
Current Report on Form 8-K filed the date hereof which is incorporated by
reference into the Registration Statement and the Prospectus Supplement and to
the use of our name under the caption "Legal Opinions" contained in the
Prospectus Supplement. In giving our consent, we do not thereby concede that we
come within the category of persons whose consent is required by the Securities
Act or the rules and regulations promulgated thereunder.

                                            Very truly yours,

                                            /s/ Willkie Farr & Gallagher LLP
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