3rd District of Columbia Infantry Battalion

The 3rd District of Columbia Infantry Battalion was an infantry battalion that served in the Union Army between April and July, 1861, during the American Civil War.

Service
The battalion was organized at Washington, D.C. Its purpose, until June, was the defence of Washington. In June, the regiment formed part of an expedition to Rockville, Maryland, passing through Seneca Mills (on June 10) and reaching Great Falls on July 7. They were then mustered out during July, 1861.