Puja Mehra has a nice piece on the tricky (and difficult to understand) history of Indian Rupee when it was linked with Sterling Pound before and after independence.
The rupee’s depreciation to more than 70 to a dollar just ahead of Independence Day led to historical comparisons of the value of the rupee. These can be misleading, as political freedom did not automatically result in India’s monetary independence in 1947. The rupee’s association with Britain was prolonged by factors beyond India’s control.
On a sterling standard 1931 onwards, the rupee, linked to a depreciating currency, depreciated along with the sterling.