December 20th, 1428 was a Saturday.
November 23rd, 1428 - December 21st, 1428
Why not celebrate an alternative birthday? In 732 days, exactly on July 27th, 2028, people who were born on December 20th, 1428 will be 219,000 days old!
Fixed holidays (Christian feast day, Earliest date for Winter solstice's eve) which are celebrated on December 20th.
| M = 1000 | CD = 400 | X = 10 | V = 5 | I = 1 |
Yes: 1428 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).