You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Tibet

Context:
In 1877, the Protestant James Cameron from the China Inland Mission walked from Chongqing to Batang in Garzê Tibetan Autonomous Prefecture, Sichuan province, and "brought the Gospel to the Tibetan people." Beginning in the 20th century, in Diqing Tibetan Autonomous Prefecture in Yunnan, a large number of Lisu people and some Yi and Nu people converted to Christianity. Famous earlier missionaries include James O. Fraser, Alfred James Broomhall and Isobel Kuhn of the China Inland Mission, among others who were active in this area.

Question:
When did a large number of Lisu people convert to Christianity?

Beginning in the 20th century