Mahāyāna (Sanskrit: महायान mahāyāna, literally the "Great Vehicle") is one of the two main existing branches of Buddhism and a term for classification of Buddhist philosophies and practice. Mahāyāna Buddhism originated in India, and is associated with the oldest historical sect of Buddhism, the Mahāsāṃghika.

The Mahāyāna tradition is the larger of the two major traditions of Buddhism existing today, the other being that of the Theravāda school. According to the teachings of Mahāyāna traditions, "Mahāyāna" also refers to the path of seeking complete enlightenment for the benefit of all sentient beings, also called "Bodhisattvayāna", or the "Bodhisattva Vehicle.

In the course of its history, Mahāyāna Buddhism spread from India to various other Asian countries such as China, Japan, Vietnam, Korea, Singapore, Taiwan, Nepal, Tibet, Bhutan, and Mongolia. Major traditions of Mahāyāna Buddhism today include Zen/Chán, Pure Land, Tiantai, and Nichiren, as well as the Esoteric Buddhist traditions of Shingon, Tendai and Tibetan Buddhism.

The Dalai Lama is a high lama in the Gelug or "Yellow Hat" branch of Tibetan Buddhism. The name is a combination of the Sino-Mongolian word далай (dalai) meaning "Ocean" and the Tibetan word བླ་མ་ bla-ma (with a silent "b") meaning "chief, high priest".

In religious terms, the Dalai Lama is believed by his devotees to be the rebirth of a long line of tulkus who are considered to be manifestations of the bodhisattva of compassion, Avalokiteśvara. Traditionally, the Dalai Lama is thought of as the latest reincarnation of a series of spiritual leaders who have chosen to be reborn in order to enlighten others. The Dalai Lama is often thought to be the leader of the Gelug School, but this position belongs officially to the Ganden Tripa, which is a temporary position appointed by the Dalai Lama who, in practice, exerts much influence. The line of Dalai Lamas began as a lineage of spiritual teachers; the 5th Dalai Lama assumed political authority over Tibet.

For certain periods between the 17th century and 1959, the Dalai Lamas sometimes directed the Tibetan government, which administered portions of Tibet from Lhasa. The 14th Dalai Lama remained the head of state for the Central Tibetan Administration ("Tibetan government in exile") until his retirement on March 14, 2011. He has indicated that the institution of the Dalai Lama may be abolished in the future, and also that the next Dalai Lama may be found outside Tibet and may be female. The Chinese government was very quick to reject this and claimed that only it has the authority to select the next Dalai Lama.