The First Council: The first council was held three months after the passing away of Buddha. This meeting was convened by his immediate at Rajagaha. Maha Kassapa, the most respected and senior monk, presided at the Council.
Two very important personalities who specialized in the two areas of the teachings:
The Dharma: Ananda, Buddha's closest companion and disciple for 25 years was blessed with an extraordinary memory. Thus he was able to recite what was spoken by the Buddha.
The Vinaya: Upali, another disciple remembered all the Vinaya rules.
Only these two sections - the Dharma and the Vinaya - were recited at the First Council (no mention was made of the Abhidharma yet). Though there were no differences of opinion on the Dharma there was some discussion about the Vinaya rules.
Before his death, Buddha told Ananda that if the Sangha wished to amend some minor rules, they could do so. However, Ananda forgot to ask the Buddha what the minor rules were. The members of the Council tried but were unable to agree on what constituted the minor rules. Maha Kassapa finally came up with the solution that no disciplinary rule laid down by the Buddha should be changed and no new ones introduced. Maha Kassapa did say one thing, however: "If we changed the rules, people will say that Gautama's disciples changed the rules even before his funeral fire has ceased burning." At the Council, the Dharma was divided into various parts and each part was assigned to an Elder and his pupils to commit to memory. The Dharma was then passed on from teacher to pupil orally. The Dharma was recited daily by groups of people who regularly crosschecked with each other to ensure that no omissions or additions were made.
The Second Council: The Second Council met a hundred years after Buddha's death. It was convened in order to discuss some Vinaya rules. However, no controversy about the Dharma was reported. The orthodox monks (Sthavarivada) insisted that nothing should be changed, while the others insisted on modifying some of the rules. At the end, a group of monks left the Council and formed the Mahasanghika - the Great Community. It must be noted that the Mahasanghika should not to be confused with Mahayana tradition.
According version says that the Second Council may have had two parts: initially in Vaisali, some 60 years after the Buddha's death and 40 years after that, a meeting in Pataliputra, where Mahadeva maintained five theses on the Arhat. The actual split may have occurred at Pataliputra and not Vaisali over details of the Vinaya. In the non-Theravadin version of events, the Mahasangha followed the original vinaya and the Sthaviravada (the Elders) wanted changes. The actual events may never be revealed, but the first split in the Sangha was a fact.
The Third Council: It was convened in the third century BC during the reign of Emperor Ashoka. This council was held to discuss the differences of opinion among the bhikkhus of different sects. However, the differences of opinion were not merely confined to the Vinaya but also concerned the Dharma. The President of the Council, Moggaliputta Tissa, compiled a book called the Kathavatthu which refuted the heretical, false views and theories held by some sects occurring at the time. The teaching approved and accepted by this Council became known as Sthaviras or Theravada, "Teaching of the Elders". The Abhidhamma Pitaka was included at this Council. After the Third Council, King Ashoka sent missionaries to Sri Lanka, Kanara, Karnataka, Kashmir, the Himalayan region and Burma. Ashoka's son, Mahinda, brought the Tripitaka to Sri Lanka, along with the commentaries that were recited at the Third Council. These teachings later became known as the "Pali-canon".
The Fourth Council: The Fourth Buddhist Council was held with the backing of King Kaniska at Jalandhar or in Kashmir around 100 CE. It was during this council that 499 monks of the Sarvastivadin School compiled a new canon. However, this council was never recognized by the Theravada school.
The Fifth Council (Burma): The 5th Buddhist Council was held from 1868 to 1871 in Mandalay, Burma where the text of the Pali Canon was revised and inscribed on 729 marble slabs.
The Sixth Council (Burma): The 6th Buddhist Council was held at Rangoon, Burma in 1954-1956.