Exhibit 99.1

Unaudited Pro Forma Condensed Statements of Operations

of Endeavour International Corporation

(Amounts in thousands, except per share data)

The accompanying pro forma financial statements are presented in accordance with Article 11 of Regulation S-X. The following unaudited pro forma condensed statement of operations reflects adjustments to give affect to the following:

• Endeavour International Corporation’s (“Endeavour”) sale of our Norwegian subsidiary, Endeavour Energy Norge AS, and a revolving credit facility between Endeavour Operating Corporation, a wholly-owned subsidiary of Endeavour, and Endeavour Energy Norge AS for cash consideration of $150 million (the “Norway Sale”).

• The income statement data assume that the Norway Sale was consummated on January 1, 2006.

We expect to recognize a gain related to the Norway Sale of approximately $47 million, after the allocation of $68 million of goodwill to the assets sold.

The capacity and amounts available under our senior bank facility is subject to a number of considerations, including certain borrowing base limitations. Upon any sale of assets that are included in the borrowing base, such as the Norway Sale, a borrowing base redetermination is required. Subsequent to March 31, 2008, we have repaid approximately $38.8 million of principal, inclusive of the amount required following the Norway Sale, thereby reducing the amount outstanding under the senior bank facility to $63.5 million.

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Endeavour International Corporation

Unaudited Pro Forma Condensed Statement of Operations

For the Year Ended December 31, 2008

(Amounts in thousands, except per share data)

				Pro Forma
	Endeavour			Adjustments			Pro Forma
Revenues	$	260,441		$	89,660		$	170,781
Expenses:
Operating expenses		46,576			14,259			32,317
Depreciation, depletion and amortization		81,734			14,408			67,326
Impairment of oil and gas properties		36,970			—			36,970
General and administrative		19,636			3,704			15,932
Total expenses		184,916			32,371			152,545
Operating Profit		75,525			57,289			18,236
Other Income (Expense):
Derivatives:
Unrealized gain		76,666			—			76,666
Realized loss		(28,578	)		—			(28,578	)
Interest expense		(22,548	)		427			(22,975	)
Other		12,154			5,528			6,626
Total Other Income		37,694			5,955			31,739
Income Before Income Taxes		113,219			63,244			49,975
Income Tax Expense		56,729			32,613			24,116
Net Income		56,490			30,631			25,859
Preferred Stock Dividends		10,809			—			10,809
Net Income to Common Stockholders	$	45,681		$	30,631		$	15,050
Net Income Per Common Share:
Basic	$	0.36					$	0.12
Diluted	$	0.32					$	0.12
Weighted Average Number of Common Shares Outstanding:
Basic		128,312						128,312
Diluted		178,312			(50,000	) (A)		128,312

(A) To adjust diluted weighted average number of common shares outstanding for anti-dilutive securities.

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Endeavour International Corporation

Unaudited Pro Forma Condensed Statement of Operations

For the Year Ended December 31, 2007

(Amounts in thousands, except per share data)

				Pro Forma
	Endeavour			Adjustments			Pro Forma
Revenues	$	176,064		$	40,188		$	135,876
Expenses:
Operating expenses		41,044			13,781			27,263
Depreciation, depletion and amortization		76,850			7,868			68,982
Impairment of oil and gas properties		—			—			—
General and administrative		19,878			4,025			15,853
Total expenses		137,772			25,674			112,098
Operating Profit		38,292			14,514			23,778
Other Income (Expense):
Derivatives:
Unrealized loss		(89,132	)		—			(89,132	)
Realized gain		12,048			—			12,048
Interest expense		(18,742	)		540			(19,282	)
Other		(723	)		(958	)		235
Total Other Expense		(96,549	)		(418	)		(96,131	)
Income (Loss) Before Income Taxes		(58,257	)		14,096			(72,353	)
Income Tax (Benefit) Expense		(9,180	)		13,028			(22,208	)
Net Income (Loss)		(49,077	)		1,068			(50,145	)
Preferred Stock Dividends		11,238			—			11,238
Net Loss to Common Stockholders	$	(60,315	)	$	1,068		$	(61,383	)
Net Loss Per Common Share:
Basic	$	(0.49	)				$	(0.50	)
Diluted	$	(0.49	)				$	(0.50	)
Weighted Average Number of Common Shares Outstanding:
Basic		123,118						123,118
Diluted		123,118						123,118

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Endeavour International Corporation

Unaudited Pro Forma Condensed Statement of Operations

For the Year Ended December 31, 2006

(Amounts in thousands, except per share data)

				Pro Forma
	Endeavour			djustments			Pro Forma
Revenues	$	54,131		$	29,250		$	24,881
Expenses:
Operating expenses		15,568			11,091			4,477
Depreciation, depletion and amortization		20,164			6,333			13,831
Impairment of oil and gas properties		849			—			849
General and administrative		21,924			4,684			17,240
Total expenses		58,505			22,108			36,397
Operating Profit (Loss)		(4,374	)		7,142			(11,516	)
Other Income (Expense):
Derivatives:
Unrealized gain		34,531			—			34,531
Realized gain (loss)		—			—			—
Interest expense		(7,941	)		630			(8,571	)
Other		(5,141	)		(522	)		(4,619	)
Total Other Income (Expense)		21,449			108			21,341
Income Before Income Taxes		17,075			7,250			9,825
Income Tax Expense		23,913			9,043			14,870
Net Loss		(6,838	)		(1,793	)		(5,045	)
Preferred Stock Dividends		1,991			—			1,991
Net Loss to Common Stockholders	$	(8,829	)	$	(1,793	)	$	(7,036	)
Net Loss Per Common Share:
Basic	$	(0.10	)				$	(0.08	)
Diluted	$	(0.10	)				$	(0.08	)
Weighted Average Number of Common Shares Outstanding:
Basic		86,636						86,636
Diluted		86,636						86,636

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