Because of the swift Venetian reaction, the Hungarian threat to Dalmatia did not materialize. Instead, a Venetian-Hungarian alliance, the so-called Conventio Amicitiae, was negotiated and directed against the Normans, probably in 1098. The Conventio Amicitiae was essentially a pact of common aggression, and thus far it was in accordance with Byzantine interests that were implacably opposed to Norman expansion. However, the agreement was underpinned by the mutual recognition by each signatory of the other’s sphere of influence in the coastal lands of the northern Adriatic: Hungary in Croatia, and Venice in the maritime cities of Dalmatia. This formalization, which was not recognized by the Byzantine emperor and made no mention of his de iure authority in Dalmatia, would have disturbed Alexius I Comnenus. Henceforth, the Venetians, who had received great rewards as imperial allies, were treated with greater caution and reserve, and the emperor steered a course between their interests and those of his occasional ally, the king of Hungary.

From Paul Stephenson’s Byzantium’s Balkan Frontier: A Political Study of the Northern Balkans, 900-1204, Cambridge: Cambridge University Press, 2000, p. 197.