Altan Khan, the king of the Tümed Mongols, first invited Sonam Gyatso, the head of the Gelugpa school of Tibetan Buddhism (later known as the third Dalai Lama), to Mongolia in 1569 and again in 1578, during the reign of the Tsangpa family. Gyatso accepted the second invitation. They met at the site of Altan Khan's new capital, Koko Khotan (Hohhot), and the Dalai Lama taught a huge crowd there.