This prosopographical study provides information about each Venetian living in the early Middle Ages, from the invasion of the Lombards in 569 - an action that forced part of the North-East Italy's population to seek refuge in the islands of the Venetian lagoon - to the rule of Duke Petrus Ursoylus II (991-1008). There is an entry for each individual listing all available information and quoting the full text of primary sources within the footnotes. The data are organized in categories such as families, first names, rulers, women, office holders, ecclesiastics, occupations, and places of residence (Venice was a duchy with different urban centers). Venice is an extremely important place for this kind of analysis. It is the area in which family name use began for the first time in medieval Europe. Venice was never conquered by a 'Germanic' people, and therefore it is possible to study the evolution of a post-Roman/Byzantine society by analyzing the names of the Venetians. Moreover, scholars interested in later periods will be able to find the origins of all the most important Venetian families.