Answer : 1. "Mir Jafar"
Explanation :

1. After the battle of Plassey, Mir Jafar was made the Nawab of Bengal.

2. After the defeat of Siraj-ud-Daula in the Battle of Plassey (23 June 1757), the British made Mir Jafar the Nawab of Bengal.

3. Mir Jafar was a puppet Nawab, and the British established their control over Bengal.