About Dates
At the time of the raid on Deerfield, the French were using the Gregorian calendar, which we still use today. According to this calendar, the raid took place on March 11, 1704. The English, however, were still using the Julian calendar, which was 11 days behind, hence February 29. Under the Julian calendar, the dating of the New Year began on March 25. Aware of the fact that the rest of western Europe dated the beginning of the New Year on January 1, the English usually wrote the date February 29, 1703/04.