December 29th, 1264 was a Monday.
December 22nd, 1264 - January 20th, 1265
Why not celebrate an alternative birthday? In 842 days, exactly on November 14th, 2028, people who were born on December 29th, 1264 will be 279,000 days old!
Fixed holidays (Christian feast day) which are celebrated on December 29th.
| M = 1000 | C = 100 | L = 50 | X = 10 | IX = 9 | IV = 4 | I = 1 |
Yes: 1264 is a leap year, therefore has a 29th of February with an additional leap day and a total of 366 days (instead of the usual 365 days in a normal year).