Ajatashatru (अजातशत्रु - Ajātaśatru, rendered in Pali as Ajātasattu, literally meaning “One Whose Enemy Is Unborn”; in Tibetan as མ་སྐྱེས་དགྲ། ma skyes dgra Makyé Dra; and in Chinese as 阿阇世王 / 阿闍世王 - Asheshi Wang, universally revered across India, Sri Lanka, Thailand, Burma, Tibet, China, Korea, Japan, Vietnam, and the global Buddhist world as the repentant monarch of Magadha who sponsored the First Buddhist Council at Rajgir), acclaimed throughout Asian Buddhist history since the 5th century BCE as the dramatic embodiment of karmic remorse, spiritual transformation, and royal patronage of the Dharma, stands as a pivotal figure in early Buddhism. Born in the 6th century BCE (with traditional chronologies placing his year of birth around 525 BCE and his year of death around 460 BCE, ruling Magadha from 492 BCE until 460 BCE during the final decade of Shakyamuni Buddha's life c. 563–483 BCE), Ajatashatru was born into the Haryanka dynasty in Rajgir (Rajagriha) in northeastern India as the son of King Bimbisara and Queen Vaidehi (Kosala Devi).
During his youth as crown prince of Magadha, Ajatashatru fell under the manipulative sway of Shakyamuni Buddha's jealous cousin Devadatta, who dazzled the young prince with psychic displays and incited him to seize the royal throne prematurely—persuading Ajatashatru around 492 BCE to overthrow and imprison his virtuous father King Bimbisara in a sealed dungeon to starve him to death, while simultaneously aiding Devadatta's repeated plots against Shakyamuni Buddha, including dispatching royal archers and releasing the intoxicated elephant Nalagiri in the streets of Rajgir.
On the very day that King Bimbisara died in his dungeon cell, Ajatashatru's chief consort gave birth to his own first son, Udayabhadda; overwhelmed simultaneously by sudden paternal love and the horrifying realization of his father's lifelong devotion to him—which Queen Vaidehi tearfully recounted—Ajatashatru ordered his father's immediate release, only to learn that King Bimbisara had just passed away, plunging Ajatashatru into agonizing grief, insomnia, and terror over the inescapable law of karma and rebirth across the six realms of samsara.
On a luminous full-moon night in Rajgir, tormented by remorse and seeking spiritual solace, Ajatashatru rejected the fatalistic doctrines of six rival sectarian teachers and followed the counsel of his wise court physician Jivaka to visit Shakyamuni Buddha at Jivaka's Mango Grove (Jivakambavana). Approaching the serene assembly of one thousand two hundred and fifty silent monks with deep awe, Ajatashatru questioned Shakyamuni Buddha on the visible, immediate fruits of the contemplative life (Samannaphala Sutta), listened raptly to the Blessed One's progressive exposition of ethical conduct, precepts, mindfulness, concentration, meditation, and wisdom, confessed his grievous patricide openly, and took lifelong refuge in the Buddha, the Dharma, and the Sangha—prompting Shakyamuni Buddha to remark that had Ajatashatru not slain his virtuous father, he would have attained the stainless Dharma-eye of Stream-Entry right on that seat.
Transformed from a tyrant into a devoted, humble protector of the Dharma, Ajatashatru governed Magadha with renewed compassion and generosity, expanded his capital at Pataliputra, and—when Shakyamuni Buddha entered final parinirvana at Kushinagara in 483 BCE—received a sacred portion of the Buddha's cremation relics, enshrining them within a grand stupa at Rajgir and celebrating a magnificent relic festival.
Three months after Shakyamuni Buddha's parinirvana in 483 BCE, Ajatashatru fulfilled his most enduring service to world Buddhism by sponsoring and protecting the historic First Buddhist Council (Sangiti) at the Saptaparni Cave (Sattapanni Cave) on Mount Vebhara outside Rajgir—constructing a grand pavilion, providing daily food and requisites for the five hundred awakened Arhat elders led by Mahakashyapa, Ananda, and Upali, and safeguarding the assembly so the Vinaya Pitaka and Sutra Pitaka could be orally codified without disturbance.
Literarily and philosophically, Ajatashatru occupies a prominent place across the Pali Canon, the Tibetan Tripitaka, and the Chinese Tripitaka—featuring in the Samannaphala Sutta (Digha Nikaya 2, corresponding to Dirgha Agama 27 in Taisho Number 1 in the Chinese Tripitaka), the Mahaparinibbana Sutta (Digha Nikaya 16, corresponding to Toh Number 1 in the Tibetan Tripitaka), the Ajatashatru Kaukrityavinodana Sutra (Toh Number 216, and Taisho Number 626), and the Mahaparinirvana Mahasutra (Toh Number 119, and Taisho Number 374), where Shakyamuni Buddha heals Ajatashatru's karmic ulcers by illuminating emptiness (शून्यता - śūnyatā; སྟོང་པ་ཉིད། stong pa nyid Tongpanyid), dependent origination, anatta, and innate Buddha-nature (tathagatagarbha) aligned with Nagarjuna's Madhyamaka, Asanga's Yogacara, and Maitreya's Uttaratantra Shastra (Toh Number 4024, and Taisho Number 1611).
Guided through sincere repentance, non-attachment, loving-kindness, equanimity, right view, skillful means, and bodhicitta to transform the three poisons of greed, hatred, and delusion, Ajatashatru mitigated the severest consequences of his past karma—reborn after his death around 460 BCE only briefly in the Lohakumbhi realm before rising toward eventual Pratyekabuddha awakening as Vijitavi—and bequeathed an immortal legacy across India, Sri Lanka, Southeast Asia, Tibet, China, Korea, Japan, and Vietnam into the 21st century as the royal patron who secured the preservation of the Four Noble Truths, the Noble Eightfold Path, and the Middle Way.