Based on the cycles of the moon, the Chinese Lunar Calendar is different than the western calendar in that the beginning of the year will fall somewhere between late January and early February (not January 1st). The Chinese adopted the Western calendar in 1911 after the fall of the Qing Dynasty but the lunar calendar is still used for Chinese New Year and other traditional Chinese festivals.
Chinese Zodiac Folklore
According to one Chinese legend the 12 animals argued as to who would be the first animal in the 12-year cycle. The gods decided to hold a contest in which the animals must cross a river. The first animal to cross the river would be the first on the chart followed by the other animals according to their finish. The rat was the smallest of the animals and was expected by the other animals to finish last. Quickly the 12 animals jumped into the river but unknown to the ox, the rat had jumped on his back. As the ox was about to jump on the riverbank to claim first place, the rat jumped off his back and won the race. The pig that was very lazy ended up last. As expected, their peers often tease most children who were born in the year of the pig.
The Twelve Animals