structural:scholar_edition
Later developments

Beginning during the Gupta (c. 3rd century CE–575 CE) period a new movement began to develop which drew on previous Mahāyāna doctrine as well as new Pan-Indian tantric ideas. This came to be known by various names such as Vajrayāna (Tibetan: rdo rje theg pa), Mantrayāna, and Esoteric Buddhism or "Secret Mantra" (Guhyamantra). This new movement continued into the Pala era (8th century–12th century CE), during which it grew to dominate Indian Buddhism. Possibly led by groups of wandering tantric yogis named mahasiddhas, this movement developed new tantric spiritual practices and also promoted new texts called the Buddhist Tantras.

Philosophically, Vajrayāna Buddhist thought remained grounded in the Mahāyāna Buddhist ideas of Madhyamaka, Yogacara and Buddha-nature. Tantric Buddhism generally deals with new forms of meditation and ritual which often makes use of the visualization of Buddhist deities (including Buddhas, bodhisattvas, dakinis, and fierce deities) and the use of mantras. Most of these practices are esoteric and require ritual initiation or introduction by a tantric master (vajracarya) or guru.

The source and early origins of Vajrayāna remain a subject of debate among scholars. Some scholars like Alexis Sanderson argue that Vajrayāna derives its tantric content from Shaivism and that it developed as a result of royal courts sponsoring both Buddhism and Saivism. Sanderson argues that Vajrayāna works like the Samvara and Guhyasamaja texts show direct borrowing from Shaiva tantric literature. However, other scholars such as Ronald M. Davidson question the idea that Indian tantrism developed in Shaivism first and that it was then adopted into Buddhism. Davidson points to the difficulties of establishing a chronology for the Shaiva tantric literature and argues that both traditions developed side by side, drawing on each other as well as on local Indian tribal religion.

Whatever the case, this new tantric form of Mahāyāna Buddhism became extremely influential in India, especially in Kashmir and in the lands of the Pala Empire. It eventually also spread north into Central Asia, the Tibetan plateau and to East Asia. Vajrayāna remains the dominant form of Buddhism in Tibet, in surrounding regions like Bhutan and in Mongolia. Esoteric elements are also an important part of East Asian Buddhism where it is referred to by various terms. These include: Zhēnyán (Chinese: 真言, literally "true word", referring to mantra), Mìjiao (Chinese: 密教; Esoteric Teaching), Mìzōng (密宗; "Esoteric Tradition") or Tángmì (唐密; "Tang (Dynasty) Esoterica") in Chinese and Shingon, Tomitsu, Mikkyo, and Taimitsu in Japanese.