George Washington's birthday became a federal holiday in 1878 for government offices in the District of Columbia, and in 1885, the law was expanded to include all federal government offices. The holiday was observed on Washington's actual birthday of February 22.
"In 1968, Congress passed the Monday Holidays Act, which moved the official observance of Washington's birthday from February 22 to the third Monday in February. Some reformers had wanted to change the name of the holiday as well, to Presidents' Day, in honor of both Lincoln and Washington, but that proposal was rejected by Congress, and the holiday remained officially Washington's Birthday."
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