46 POLITICAL SCIENCE. lies from the main land of a superior class. A Venetian chronicler informs us that magnates and proceres from Aquil- eia settled in Rivolatum, of whom he gives a list amounting to fifty-three.* Three dukes reigned from 697 to 737, of whom the third was killed in a tumult (or civil war, as the chronicler calls it), in whose place was elected, as an annual magistrate, a magister militum. The choice of a magistrate with this name was not strange, for, as Heinrich Leo (Gesch. Ital., i., 247) expresses himself, i( in the regions of Ravenna and the Pentapolis magistri militum are spoken of as the highest political magistrates, and that, interchangeably with ditces. Perhaps the choice of a new dux was hindered by the strife of factions only, and the magister militum in Venetia is put forward, no doubt, as the commander "of the sc/iolce mili- tum, or military companies, because the higher office was not yet filled." Officers with this title were at the head of affairs for five years, and then the son of the slain duke, who was elected to fill the same office, was blinded and banished.f It is recorded of the next duke but one, Dominicus Monega- rius, that two tribunes were associated with him as counsel- lors, in which we discern that suspicion of the doge which appears so prominently in later Venetian history. From the year 811, for more than two centuries members of three families furnished Venice for the most part with its chief magistrates. This shows a certain tendency towards making this life-long office hereditary, or at least that the doges found it not difficult to secure the office during their life-time for one of their relatives.. In the eighth century Venice carried on a commerce with the Saracens of Africa in Christian slaves, which Pope Zachary (732-751) forbade ; and * Andrea Dandolo, doge in 1343, in Muratori, Rer. Ital. Scriptores, xii., 158. f Dandolo (Mur., xii., 156) mentions that the town of Heraclea, from which the exiled dukes originated, was destroyed by the Vene- tians, although some, says he, ascribe the act to Pepin, king of France. Pepin was in Italy about 754, just before the dtike Deus- dedit or Diodato was deposed May not the presence of the Franks in Italy have had something to do with these troubles ?