Viharas were for the purpose of living, Chaityas were assemblies for the purpose of discussions. Further, Chaityas were with Stupas, Viharas did not have stupas.
According to the Chera poets, Senguttuvan was their greatest king. He is also known as the Red or Good Chera. He led many successful military expeditions. He has also been mentioned in the post-Sangam text, Silappadikaram.
Vajji was a mahajanapada towards the north of Ganga in the division of Tirhut. It was a confederacy of eight or nine clans. The capital of Vajji mahajanapada was situated at Vaishali.
First Rajgir, Second vaishali, Third patliputraFourth Buddhist Council is the name of two separate Buddhist council meetings first in Sri Lanka and another at Sarvastivada school, in Kashmir around the First Century AD.