Today, February 29, is a Leap Day, and this year, 2012, is a Leap Year. In the tradition of the Gregorian Calendar, a day is appended to the end of February once every four years to account for the fact that the earth takes slightly more than 365 days to rotate around the sun. To be precise, it takes 365.2425 days.
Cultures throughout the word have devised different methods of compensating for the additional time, and those with lunisolar calendars observe an additional month, referred to as an embolismic month. Moreover, a variety of cultural traditions have emerged to mark the occasion of a Leap Year. Across the United Kingdom and northern Europe tradition holds that women may only propose marriage in a leap year or specifically on leap day. In fact, gender role reversal is also a common American theme, as attested in the following 1936 clipping from the Spokane Chronicle:
Browsing though Music for the Nation: American Sheet Music, 1820-1860, 1870-1885 reveals that waltzes and polkas were often written in commemoration of leap years, and several of them reflect the theme of women courting reluctant men with titles like “The Trials of Leap Year” and “I Wish You Would Propose, or The Leap Year”.
Children born to women on leap day are referred to as “leapers” or “leaplings”. Growing up in America, leaplings commonly celebrate their birthdays either on February 28 or March 1, but they are remarkable for having only a quarter as many birthdays as people born at any other point in the year. You can find out more about leap day in popular culture by browsing the many primary source materials available through Opening History.