Sir Muhammad Iqbal (1877-1938) now portrayed as the greatest thinker of the Indo-Pakistan Subcontinent, held Hazrat Mirza Ghulam Ahmad of Qadian to be “the profoundest theologian”.
Below is the image of his article where he clearly stated so:
He held this opinion for most of his life, but the last few years of his life saw a shift in his opinion. The reasons seem to be political more than religious. Ayesha Jalal has given a very interesting account of Iqbal’s political interests and his change of heart in her wonderful book Self And Sovereignty: Individual and Community in South Asian Islam since 1850.