China traces its roots as a political and cultural entity back to around 2000 BCE. From the 14th to the 17th century, it was the most advanced civilization on earth. Colonial and civil wars weakened China during the 19th century. In 1911, nationalists instituted the republic. In 1949, communist forces defeated the nationalists and established the People's Republic of China. Today, China is rapidly developing as a regional power in Asia, and an emerging power on the world scene. The traditional religions of China are Taoism and Buddhism. Christianity has long been a foreign religion with few followers. Under communist rule China became officially an atheist country. As of 1979, churches and other religious groups were gradually given more space. Delegations of the Protestant churches travelled abroad to re-establish contact with ecumenical partners. In 1948, four Chinese churches were among the founding members of the WCC. They withdrew at the time of the Korean war. Membership was resumed in 1991, by the China Christian Council. Christianity has grown and continues to grow, as do other religions, e.g. Buddhism. Estimates vary widely, from about 22 million Christians (Protestants and Catholics) to over 100 million (i.e. from 1.5 percent to 8.5 percent). The latter would include over 40 million charismatics in house churches, 14 million in unregistered house churches, five million "New Birth" movement, etc. (World Christian Database, 2005); the WCD estimate of Three-Self Christians matches the figure of 16 million of the China Christian Council. Chinese research institutions put the total number at about 65 million. There is a small minority of about 60,000 Chinese Orthodox Christians.