 In 1081, his uncle, Emperor Alexios I Komnenos, proposed a marriage match between John and a German princess to the Holy Roman Emperor Henry IV (), but nothing came of this.In early 1091, John was chosen by Alexios to replace John Doukas as the governor ("doux") of Dyrrhachium, in modern-day Albania.The city was of great importance to the Byzantine Empire, as the "key of Albania" and the main point of entry from Italy into the Balkans, a fact illustrated by the role it played in the Norman invasion in the early years of Alexios's reign.