George Washington was born on February 11, 1731. In 1752, however, Britain and her colonies changed from the Julian to the Gregorian calendar, the calendar we use today. The change added 11 days and designated January rather than March as the beginning of the year. Accordingly, Washington’s birthday was February 22, 1732.
The federal holiday was celebrated on February 22 until legislation in 1968 designated the third Monday of February the official day to celebrate Washington’s birthday. In 1971, when the 1968 Act went into effect, President Nixon proclaimed the holiday Presidents’ Day, to commemorate all past presidents, not just Washington and Lincoln. This was never intended or authorized by Congress; even so, it gained a strong hold on the public consciousness.
The states are not obliged to adopt federal holidays, which only affect federal offices and agencies. While most states have adopted Washington’s Birthday, a dozen of them officially celebrate Presidents’ Day. A number of the states that celebrate Washington’s Birthday also recognize Lincoln’s Birthday as a separate legal holiday.