On the evening of August 1, 1928, Rajendra Prasad arrived with two locals at a hall in the Austrian city of Graz to address a peace gathering. Inside the mood was frosty. “As we entered the hall, people started looking at me,” Prasad wrote years later in his autobiography. “Someone asked me if I would speak in German and I replied that I knew only English.” Prasad had been invited to Graz by one Dr Standenath, a lecturer at a local medical college who had exchanged letters with Mahatma Gandhi. Two days earlier, he had delivered a talk at an...