Feb. 28, 2011, only about 13 hours old, is already becoming a momentous day in D.C. history. Not because of any particular moment that happened this morning, but because of a major announcement affecting the preservation of D.C. history. As The Washington Post reports, real estate developer Albert Small has given his collection of Washingtoniana to George Washington University:

The collection has almost 700 pieces, including several rare maps. A letter written by George Washington to Congress in 1790 outlining the 10 square miles that would be the capital is one of the prized artifacts. The gift also includes a hand-drawn map, made by surveyor John Frederick Augustus Priggs in 1790, which shows the rivers and the road that ran from Georgetown to Anacostia called the Ferry Road.

It also includes a bandana, sold as a souvenir, with the design of the first engraved map of Washington and an 1810 cooper plate that was used to print money for the Bank of Columbia in Georgetown.

In other D.C. history notes, we’d be remiss to not mention that Sunday marked two important dates in the city’s history of governance.

First, Feb. 27, 1801, was the day Congress passed the District of Columbia Organic Act. Officially titled “An Act Concerning the District of Columbia,” the law divided the District into two counties—Washington County on the Maryland side of the Potomac and Alexandria County on the Virginia side. (Virginia later lobbied to get its half back, and the areas now known as the city of Alexandria and Arlington County retroceeded in 1846.) Each county got its own court with “one chief judge and two assistant judges resident within said district,” along with a marshal and a U.S. attorney specially assigned to District.

It also meant that those living in the District were no longer considered residents of either Maryland or Virginia. Thus, they were no longer allowed to vote for president, nor be represented by a voting member of Congress.

District residents were able to vote for president with the 1961 passage of the 23rd Amendment to the U.S. Constitution. No word yet on the whole voting representation in Congress bit.

On Feb. 27, 1871, President Ulysses S. Grant appointed Henry Cooke to be the District’s new territorial governor, as part of the District’s short-lived experimentation with territorial government.

With contributions from William F. Zeman