Calendars are funny things.
From 150 AD until 1582 (or 1752, more later) March 25 was New Years Day. Huh? Allow me to explain.
Around 150 AD Catholic church leaders decided by unanimous consent to reinvent the Roman holiday Saturnalia, the winter solstice, as the celebration of the birth of Jesus. December 25th was the agreed upon date. With me so far?
Around the same time, devotion to Jesus' mother came into vogue, and a feast day known as Lady's Day was created. Lady's Day marked the beginning of the church year. Not so coincidentally, Lady's Day, now known as Annunciation Day was placed nine months before Christmas, or March 25.
If you have ever wondered why the 8th month (oct ober) was really the 10th, or the 10th month (Dec ember) was 12 begin looking here.
Around 1582, the Gregorian calendar was instituted throughout Catholic Europe. Its big improvement was to reinstate New Years on January 1, and moved the major liturgical celebrations to a more fixed time period. It took almost 200 years for the remainder of Europe to finally get in step. England didn't change until 1752.
And there boys and girls is your history lesson for the day. How, or more importantly, why do I know this? It's my birthday.