In China's cities and the countryside, New Year pictures are closely linked with the Spring Festival (the Chinese New Year). Pasting up New Year pictures is a part of the festive celebrations.

The aim of pasting up New Year pictures is to please children and promote the values of hard work and integrity. Wood block New Year pictures reached their zenith during the Qing Dynasty (1644-1911 A.D.). Pictures of different subjects, themes and forms of expression were produced in dozens of places in the country. Block engraving, printing and color application techniques also improved during this period. The subjects of the paintings covered all aspects of social life: portraits of door gods, historical stories, fairy tales, folk customs, scenes of production and labor, lucky mascots of birds and flowers, humorous scenes, current affairs-almost everything. No wonder New Year pictures are called "encyclopedias on folklore."

Many New Year pictures depict religious themes. Door Gods, one reoccurring theme, appeared during the Tang Dynasty (618-907 A.D.). The Four Beauties, block printed pictures made in the Song Dynasty (618-907), were considered state treasures. During the Ming (1368-1644 A.D.) and Qing (1644-1911 A.D.) dynasties, the art of New Year pictures spread nationwide. According to statistics, there were more than 2,000 varieties of wood block New Year pictures in circulation. These also spread to Vietnam, Japan, Thailand and Russia.

On New Year's Eve, people pasted New Year pictures in their houses, and welcomed in the God of Wealth. The time to welcome in the God of Wealth varies from place to place. Some celebrate on the second day of the first lunar month, or on the fifth day of the first lunar month, but most celebrate at midnight on New Year's Eve. Jiaozi, a dumpling with a meat and vegetable stuffing, symbolizes the wealth sent by the god of people also paste up portraits of these deities.

There are several different versions of the origins of this custom. The most common practice was to worship Guan Yu, a famous general of the Three Kingdoms Period (220-265 B.C.), a figure from the classic novel Romance of Three Kingdoms. He was canonized due to his loyalty, bravery, persistence and selflessness, and people offered sacrifices to him to pray for wealth. This custom continues to this day.

Source: http://www.chinavista.com/experience/wood_block/wood_block.html