New Delhi, Feb. 21 -- On the evening of 30 January 1948, as an assassin's bullets shattered the winter calm at Birla House in New Delhi, the lives of Mahatma Gandhi and Ghanshyam Das Birla were bound together in tragedy.

Their association, however, long predated the tragic killing of the Mahatma. It remains one of the most unusual partnerships of the freedom movement: A devout capitalist and the apostle of moral resistance, joined by mutual trust and a shared idea of nationhood.

"Gandhiji came into my life because I went to him. I wanted to know him," Birla later recalled. "I was greatly benefited by that great soul." The benefit was mutual. Gandhi found in Birla not merely a benefactor but a businessman who believed that political free...