In which year, the nationalization of subsidiary banks of the State Bank of India (SBI) was done?

1959
In 1959, State Bank of India (subsidiary) act was passed. As per the act, seven subsidiary banks of the State Bank of India (SBI) were nationalized as a major process of nationalization. The seven subsidiary banks are State Bank of Bikaner and Jaipur (SBBJ), State Bank of Hyderabad (SBH), State Bank of Mysore (SBM), State Bank of Patiala (SBP), State Bank of Indore, State Bank of Saurashtra and State Bank of Travancore (SBT).