Dude, catch your breath, based on traffic on freeways this afternoon, NOBODY was at work, except you, of course. It's been that way around Christmas for as long as I remember, and fortunately for me, that's been a long time. Just for curiosity sake, a quick google does explain some of the holidays taken in Japan. There are more, but these are the primary ones. Here you go:
Japanese Holidays
Jan 1-3 New Year
Second Monday of January Coming of Age for 20 year olds
February 11 National Foundation Day
March 21 Spring Equinox Day
April 29 Showa Day
May 3 Constitution Day
May 4 Greenery Day
May 5 Children's Day
Third Monday of July Ocean Day
Third Monday of September Respect for the Aged Day
September 23 Autumn Equinox Day
Second Monday of October Health and Sports Day
November 3 Culture Day
November 23 Labor Thanksgiving Day
December 23 Emperor's Birthday
December 24-25 Christmas
Of course, if a national holiday falls on a Sunday, the following Monday will also be a holiday. If a day lies between two national holidays, the day will also be turned into a holiday.
Whoa, there you have it. Some of these are especially helpful, especially Culture Day.
Hope you have a great Christmas season.