Je Tsongkhapa in the context of Dignāga

The Gelug (/ɡəˈluːɡ/, also Geluk; lit. 'virtuous') is the youngest of the four major schools of Tibetan Buddhism. It was founded by Je Tsongkhapa (1357–1419), a Tibetan philosopher, tantric yogi and lama and further expanded and developed by his disciples (such as Khedrup Je, Gyaltsap Je, Dulzin Drakpa Gyaltsen, and Gendün Drubpa).

The Gelug school is alternatively known as Kadam (bKa’-gdams gsar-pa), since it sees itself as a continuation of the Kadam tradition of Atisha (c. 11th century). The school of New Kadam, or New Kadampa is an offshoot of the Gelug-tradition. Furthermore, it is also called the Ganden school, after the first monastery established by Tsongkhapa. The Ganden Tripa ("Ganden Throne Holder") is the official head of the school, though its most influential political figure is the Dalai Lama ("Ocean Teacher"). Allying themselves with the Mongol Khans, the Gelug school emerged as the dominant Buddhist school in Tibet and Mongolia since the end of the 16th century (religiously and politically). Another alternative name for this tradition is the Yellow Hat school or sect.

The 1st Dalai Lama, Gedun Drupa (Tibetan: དགེ་འདུན་གྲུབ་པ།, Wylie: dge 'dun grub pa; 1391–1474) was a student of Je Tsongkhapa, and became his first Khenpo (Abbott) at Ganden Monastery. He also founded Tashi Lhunpo Monastery in Shigatse. He was posthumously awarded the spiritual title of Dalai Lama.

Khedrup Gelek Pelzang, 1st Panchen Lama (1385–1438 CE) – better known as Khedrup Je –  was one of the main disciples of Je Tsongkhapa, whose reforms to Atiśa's Kadam tradition are considered the beginnings of the Gelug school of Tibetan Buddhism.

Khedrub Je is considered to be an emanation of Manjusri, the Buddha of Wisdom.

Gyaltsab Je (Tibetan: རྒྱལ་ཚབ་རྗེ་, Wylie: Rgyal tshab rje) (1364 – 1432) or more elaborately, Gyaltsab Dharma Rinchen was born in the Tsang province of central Tibet. He was a famous student of Je Tsongkhapa, and actually became the first Ganden Tripa (throne holder) of the Gelug tradition after Je Tsongkhapa's death. He also studied with Rendawa Zhonnu Lodro (red mda' ba gzhon nu blo gros, 1349–1412).

Gyaltsab Je was a prolific writer; one of his most famous texts is a commentary of Shantideva's A Guide to the Bodhisattva's Way Of Life. Lodrö Tenpa, the seventh Ganden Tripa, was his student.

The Rimé movement (Tibetan Wylie: ris med; approximate pronunciation "reemay") also written in some English sources as Rime, Ri-me, Rimay) is a movement or tendency in Tibetan Buddhism which promotes non-sectarianism and universalism. Teachers from all branches of Tibetan Buddhism – Nyingma, Kagyu, Sakya, Gelug, Jonang – and from Bon have been involved in the promoting of Rimé ideals.

According to Sam van Schaik, eclectic and non-sectarian tendencies existed in Tibetan Buddhism before the 19th century, and figures like Tsongkhapa, Longchenpa and Shabkar are widely known to have studied with teachers from different traditions. However, political divisions and religious sectarianism increased during a period of warfare in the sixteenth and seventeenth centuries. This was a time when the Gelug school was the politically dominant religion and Gelug lamas were also the political leaders of Tibet (see Ganden Phodrang).