Explanation:

- The nationalization of commercial banks in India took place to give the government greater control over credit delivery.

- 1969: The first significant nationalization of banks took place in 1969, covering 14 major banks.

- 1966: No major bank nationalization event occurred in this year.

- 1968: This year did not witness any major nationalization of commercial banks.

- 1967: There was no nationalization of banks in this year.

.