Most Memorable Presidential Birthdays

The irony of Presidents' Day is that we don't know exactly when George Washington was born — either Feb. 11 or 22. At the time of his birth in the 1730s, the Julian calendar was still being used by the British Empire, who didn't switch to the Gregorian until later in the 18th century. But regarless of when he was actually born, the federal holiday is an undisputed gift to all school children and fully employed individuals who get the day off.

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Little is known about how Washington celebrated his special day, but presidents since have shown their constituents one thing: They like to party. Marilyn Monroe set the bar when she serenaded President Kennedy in 1962, with a version of "Happy Birthday" that would become the standard. Fifty years later, Lady Gaga did her best Monroe impersonation, nearly giving President Clinton a heart attack on his 65th — or so he says.

Presidents probably know more secrets than anyone, so it can be difficult to surprise them, but White House staffers have done just that for President George W. Bush and President Reagan. The former's party occurred on Air Force One en route to Japan for the G-8 Summit. The latter was punctuated by a stirring rendition of "Seventy-Six Trombones" and Reagan forgetting his age. Maybe that party wasn't too memorable for him.

Last year, President Obama used his birthday as an excuse to throw a party — for his political donors in Chicago. Over the course of the evening he hosted not one but two events, which netted him nearly half a million dollars.

President Truman got a timely gift for his 61st birthday on May 8, 1945, when he announced that World War II had ended. And if birthday well-wishers are a sign of presidential popularity, then President Franklin Roosevelt was obviously the most liked of them all. On his 52nd in 1934, he was flooded with 100,000 telegrams, including one that measured 1,250 feet and was signed by 40,000 people.