Short answers, pulled from the story.
A Gana-Sangha, also called a Gana-Rajya or Tribal Assembly, was a type of aristocratic republic in ancient India governed by a deliberative assembly rather than a king. The assembly held financial, administrative, and judicial authority, and a chief elected from the noble Kshatriya class coordinated decisions with it. These political structures existed as early as the 6th century BC.
Among the sixteen great states known as the mahajanapadas, Vajji and the Mallakas followed Gana-Sangha rule. Smaller states including the Koliyas and the Shakyas, the tribal state where Gautama Buddha was born, also used the assembly form of government.
The Gana-Sanghas were located at the foothills of the Himalayas, near what is today eastern Uttar Pradesh, Bihar, and the Terai region of Nepal. They occupied the geographical and cultural periphery of ancient India, while monarchical states controlled the Ganges flood plains below.
Scholars disagree. Some emphasize the assemblies' broad deliberative role and consider them early democracies; others point to the fact that rulers always came from the Kshatriya warrior class and argue they were oligarchies or aristocracies. The Licchavis of Vajji had a governing body of 7,077 rajas, while the Shakyas and Koliyas allowed all men, rich and poor, into their assemblies.
Gana-Sanghas are generally believed to have existed from as early as the 6th century BC and persisted in some areas until the 4th century BC.
The Arthashastra, an ancient Indian handbook for monarchs sometimes called "The Prince of Ancient India", contains a chapter on dealing with sanghas that includes instructions for manipulating their noble leaders. It says nothing about influencing ordinary citizens, which scholars read as evidence that Gana-Sanghas were aristocratic or oligarchical bodies rather than broad-based democracies.