Why and by whom was Khalifat …

The Khilafat Movement was launched by Muhammad Ali and Shaukat Ali. Gandhiji saw this as an opportunity to bring Muslims under the umbrella of a unified national movement. At the Calcutta Session of the Congress in September 1920, he convinced other leaders to start a Non-Cooperation Movement in support of Khilafat Movement.
The Khilafat Movement (1919-1924), was a pan-Islamic, political protest campaign launched by Muslims in British India to influence the British Government and to protect the Ottoman empire during the aftermath of First World War. The First World War had ended with the defeat of Ottoman Turkey.
There was a fear that the power of the spiritual head of the Islamic world (Khalifa) would be curtailed. To defend his power, a Khilafat Committee was formed in Bombay in 1919. The Khilafat leaders put pressure . upon the British Government to give better treatment to Turkey.