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:
Sino-Tibetan_relations_during_the_Ming_dynasty

Context:
In 1207, the Mongol ruler Genghis Khan (r. 1206–1227) conquered and subjugated the ethnic Tangut state of the Western Xia (1038–1227). In the same year, he established diplomatic relations with Tibet by sending envoys there. The conquest of the Western Xia alarmed Tibetan rulers, who decided to pay tribute to the Mongols. However, when they ceased to pay tribute after Genghis Khan's death, his successor Ögedei Khan (r. 1229–1241) launched an invasion into Tibet.

Question:
Who invaded Tibet? 

Ögedei Khan