Henry III assumed the throne in the middle of his birthday party.
In the United States between 1973 and 1999, September 16 is the most common birthday in the United States and December 25 the least common birthday (other than February 29, because of leap years)
 Kim Il-sung's birthday, Day of the Sun, is the most important public holiday of the country, and Kim Jong-il's birthday is celebrated as Day of the Shining Star

