of Teachings) helped in disseminating the values of Buddhism in powerful state affairs as well as in the Tibetan culture. The Bka'-'gyur has six main categories in the book: (1) Tantra, (2) Prajñāpāramitā, (3) Ratnakūṭa Sūtra, (4) Avatamsaka Sutra, (5) Other sutras, (6) Vinaya. The Bstan-'gyur is a compilation work of 3,626 texts and 224 volumes which basically encompass texts of hymns, commentaries and tantras. The Sakya (Grey Earth) school, was founded by Khön Könchok Gyelpo (1034–1102), a disciple of the great scholar, Drogmi Shākya. It is headed by the Sakya Trizin, and traces its lineage to the mahasiddha Virūpa. Other influential Indian teachers include Tilopa (988–1069) and his student Naropa (probably died ca. 1040). Their teachings, via their student Marpa, are the foundations of the Kagyu (Oral lineage) tradition, which focuses on the practices of Mahamudra and the Six Dharmas of Naropa. One of the most famous Kagyu figures was the hermit Milarepa, an 11th-century mystic. The Dagpo Kagyu was founded by the monk Gampopa who merged Marpa's lineage teachings with the monastic Kadam tradition. All the sub-schools of the Kagyu tradition of Tibetan Buddhism surviving today, including the Drikung Kagyu, the Drukpa Kagyu and the Karma Kagyu, are branches of the Dagpo Kagyu. The Karma Kagyu school is the largest of the Kagyu sub-schools and is headed by the Karmapa. Mongol dominance (13th–14th centuries) Tibetan Buddhism exerted a strong influence from the 11th century CE among the peoples of Inner Asia, especially the Mongols. The Mongols invaded Tibet in 1240 and 1244. They eventually annexed Amdo and Kham and appointed the great scholar and abbot Sakya Pandita (1182–1251) as Viceroy of Central Tibet in 1249. In this way, Tibet was incorporated into the Mongol Empire, with the Sakya hierarchy retaining nominal power over religious and regional political affairs, while the Mongols retained structural and administrative rule over the region, reinforced by the rare military intervention. Tibetan Buddhism was adopted as the de facto state religion by the Mongol Yuan dynasty (1271–1368) of Kublai Khan. It was also during this period that the Tibetan Buddhist canon was compiled, primarily led by the efforts of the scholar Butön Rinchen Drup (1290–1364). A part of this project included the carving of the canon into wood blocks for printing, and the first copies of these texts were kept at Narthang monastery. From family rule to Ganden Phodrang government (14th-18th centuries) With the