Bimbisara was succeeded by his son Ajatashatru.
Ajatashatru killed his father and seized the
throne.
Ajatashatru followed a moper aggressive policy . He gained complete
control over Kashi and Broke the earlier amicable relations by attacking his
maternal uncle Prasenjit, the king of Kosala.
The Vajji confederation was Ajatashatru ‘s next target of attack .
The was
a lengthy one
and tradition tells
us that after a long period of 16 years , he was able to defeat the Vajji only
though deceit, by sowing the seeds of discord among the people of Vajji.
The three things who played important role to defeat the Vajji_ (i)
Sunidha and Vatsakar _ Ajatashatru’s
diplomatic
ministers . who sowed the seeds of discord among Vajjis, (ii) Rathamusala_ a
kind of engine which catapulted big stones.
In this way Kashi and Vaishall
(the capital of Vajji) were added to Magadha, making it the most powerful territorial power in the Ganges Valley.
He built the fort of Rajagriha and a watch –fort (Jaladurga)
at a village called Patali, on the banks
of the Ganges.