Who had convened the second Buddhist council at Vaishali?

The correct answer is: Ajatshatru.

The Second Buddhist Council was convened by Ajatshatru, the king of Magadha, in 383 BCE at Vaishali. The council was called to resolve a dispute between the Sthavira and Mahasanghika schools of Buddhism. The council lasted for nine months and resulted in the production of the Kathāvatthu, a collection of debates between the two schools.

Ajatshatru was a powerful and influential king who played a major role in the development of Buddhism. He was the son of Bimbisara, the founder of the Magadha Empire, and the father of Ashoka, the Mauryan emperor. Ajatshatru was a devout Buddhist and he supported the construction of many Buddhist monasteries and stupas. He also played a role in the spread of Buddhism to other parts of India.

The Sthavira and Mahasanghika schools were two of the earliest schools of Buddhism. The Sthavira school was the more conservative of the two schools, while the Mahasanghika school was more open to new ideas. The dispute between the two schools centered on the interpretation of the Buddha’s teachings. The Sthavira school believed that the Buddha’s teachings were to be interpreted literally, while the Mahasanghika school believed that the Buddha’s teachings could be interpreted more flexibly.

The Second Buddhist Council was a major event in the history of Buddhism. It helped to resolve the dispute between the Sthavira and Mahasanghika schools and it also helped to spread Buddhism to other parts of India.