2 Interesting Christmas Facts You Probably Didn't Know Before This 1-Christmas wasn't always on December 25.Though Christmas celebrates the birth of Jesus Christ, there is no mention of December 25 in the Bible. Most historians actually believe Jesus was born in the spring, not the winter. And his birthday itself didn't become the official holiday until the third century. Some historian posit that the date was actually chosen because it coincided with the pagan festival of Saturnalia, which hon (11/2019)