Question

The birth of Pakistan instigated the biggest mass migration in human history. It occurred in which decade?

Answer 1

birth of pakistan was proposed by mahommed ali jinnah at almost end of british raj from india
and this migration spanned from almost 1946-1948
so taking about decade you can say 1940-1950

Answer 2

It was the Britishers who came up with the suggestion of partitioning India and Pakistan.

The reason behind the partition was to reduce the bloodshed between the Hindus and the Muslims. Pakistan was born before the partitioning.

It was in the 1940s  that Pakistan came into existence. But, the partitioning of India and Pakistan took place in the year 1947 after a lot of struggle.

The result of this partitioning can still be seen as disputes between the two countries.