The following important events in the history of the District of Columbia affected political boundaries, record keeping, and family movements.

1788-1791	Maryland ceded parts of Montgomery (including Georgetown) and Prince George counties to the United States, and Virginia ceded part of Fairfax county (including the town of Alexandria). Those counties continued to govern the area until about 1801, but Virginia kept permanent custody of the records for Alexandria.
1800	Congress, the President, and a staff of about 140 people moved from Philadelphia to Washington.
1801	Two counties were established in the District: Washington County, east of the Potomac, and Alexandria County, on the west side of the river. The City of Washington was incorporated in 1802. Georgetown wills and deeds continued to be registered in Montgomery County, Maryland, until the late nineteenth century.
1814	During the War of 1812, the British captured Washington and burned most of the public buildings and records.
1846	The portion originally given by Virginia was returned to that state.
1861-1865	Although defended by federal troops during the Civil War, Washington was several times threatened by Confederates. The civilian population of Washington more than doubled during the 1860s.
1871	Congress changed the city's status to that of a federal territory.
1895	Georgetown was merged into the city of Washington. The boundaries of Washington became coextensive with those of the District of Columbia.