Zenith National Insurance (ZNT) 10-K 2004 FY Annual report

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Exhibit 21

SUBSIDIARIES OF THE REGISTRANT

ZENITH NATIONAL INSURANCE CORP. AND SUBSIDIARIES
(As of December 31, 2004)

Zenith National Insurance Corp. (a Delaware corporation)
	Zenith National Insurance Capital Trust I (a Delaware statutory trust)
	Zenith Development Corp. (a Nevada corporation)
	Zenith Insurance Company (a California corporation)
		Zenith Star Insurance Company (a Texas corporation) ZNAT Insurance Company (a California corporation) Zenith Insurance Management Services, Inc. (a Florida corporation) 1390 Main Street LLC (a Delaware Limited Liability Company) Zenith of Nevada, Inc. (a Nevada corporation)

Each subsidiary shown is wholly-owned by the subsidiary shown in the tier above it.

Zenith Insurance Company owns approximately 20.9% of the outstanding shares of Advent Capital (Holdings) PLC, a U.K. company.

CalRehab Services, Inc. (a California corporation) was dissolved in 2004.

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Exhibit 21

SUBSIDIARIES OF THE REGISTRANT