Statistics for occurrence #1 of “Fortress Monroe” in chapter 40 of Admiral David D. Porter, The Naval History of the Civil War.:

...ebruary, 1864, Acting-Rear-Admiral S. P. Lee, commanding the North Atlantic squadron, was in co-operation with Major-General B. F. Butler, who commanded the army of the James with his headquarters at Fortress Monroe . General Meade commanded the Army of the Potomac, with his headquarters south of the Rapidan, while the headquarters of the Army of the Shenandoah, under command of Major-General Sigel, were at Winch...
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Fortress Monroe (Virginia, United States) 7,630 72 276 0 0 user votes

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