Christmas in Japan has an on-again, off-again history that dates back more than 450 years.
Now, Christmas is as big an event in Japan as it is in much of the rest of the world, even if the Christian message behind the season is not as strong as in other places.

According to the Japan Anniversary Association, Christmas contributes about 700 billion yen to the Japanese economy, making the festive season an important occasion for businesses.

But it wasn't always this way. Japan's first recorded Christmas occurred in a small church in Suo, in what is now called Yamaguchi Prefecture, in 1552. A Jesuit priest called Gomez de Torreres wrote about saying a Christmas Mass for Japanese believers.

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Why dont you ask japanese why they enjoys christmas.
or as them what is christmas.

Eh, that's not really the case. Christmas kind of romanticized and is more like Valentines day in Japan.

The big holiday is Oshogatsu (new years). When you're a kid you get to go see your relatives and get money.

The big holiday is Oshogatsu (new years). When you're a kid you get to go see your relatives and get money.

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This kind of thing also happen in chinese family in Thailand