Although he met with many other artistic personalities also based in Switzerland during the war (including Stefan Zweig, who noted his extensive drinking, and James Joyce), Busoni soon found his circumstances limiting. After the end of the war, he again undertook concert tours in England, Paris and Italy. In London, he met with the composer Kaikhosru Shapurji Sorabji who played his Piano Sonata No. 1 for him (he had dedicated it to Busoni). Busoni was sufficiently impressed to write a letter of recommendation for Sorabji. When Busoni's former pupil Leo Kestenberg, by then an official at the Ministry of Culture in the German Weimar Republic, invited him to return to Germany with the promise of a teaching post and productions of his operas, he was very glad to take the opportunity.