It was at the CafÃ Anglais in 1867 that DuglÃ rÃ served a famous meal that became known as the DÃ ner des trois empereurs , for Tsar Alexander II of Russia , his son the tsarevitch ( who later became Tsar Alexander III ) and King William I of Prussia , as well as Prince Otto von Bismarck who were in Paris for L'Exposition Universelle . It was here in 1867 that DuglÃ rÃ served a famous meal that became known as the DÃ ner des trois empereurs , ( ` Dinner of the Three Emperors ' ) for Tsar Alexander II of Russia , his son the tsarevitch ( who later became Tsar Alexander III ) and King William I of Prussia , as well as Prince Otto von Bismarck who were in Paris for L'Exposition Universelle .