Christians celebrate Christmas Day as the anniversary of the birth of Jesus of Nazareth, a spiritual leader whose teachings form the basis of their religion. Popular customs include exchanging gifts, decorating Christmas trees, attending church, sharing meals with family and friends and, of course, waiting for Santa Claus to arrive. December 25–Christmas Day–has been a federal holiday in the United States since 1870. The middle of winter has long been a time of celebration around the world. Centuries before the arrival of the man called Jesus, early Europeans celebrated light and birth in the darkest days of winter. Many peoples rejoiced during the winter solstice, when the worst of the winter was behind them and they could look forward to longer days and extended hours of sunlight.