As a composer Lehár started with contributions to the opera-genre but the great triumph of his first operetta 'Die lustige Witwe', (The merry widow), in 1905 made him clear that he had to gif his talents to the operetta. 'Das Land des Lächelns' (1929) was composed for the famous tenor Richard Tauber. The plot deals with the love between the Chinese Prince Sou-chong and Lisa, daughter of Count Lichtenfels. Besides the exuberant aria 'Dein ist mein ganzes Herz', became Sou-chong's intimate entrance aria 'Immer nur lächeln' very popular.