Then Pietro the younger turned pirate himself, and armed six fast vessels and harassed the Venetian traders all down the Adriatic. But meanwhile he still had a strong party of friends for him in Venice, and their influence grew quickly, even with the people, and many secret influences which we can no longer trace were brought to bear for him; until at last the Venetians themselves, who had tried to murder him, decreed him the ducal crown and the supreme power, and recalled him and deposed his aged father. The old man died within a few weeks, and all he could bequeath to his wife was ‘a vineyard surrounded by walls’ on the shore of San Pietro; and Pietro Candiano IV. ruled alone.
He did outrageous deeds to strengthen his power. To win the protection of the Emperor Otho he forced his wife to take the veil in the convent of Saint Zacharias, and obliged his only son by her, Vitale, to become a monk. Having thus disposed of them, he took to wife Gualdrada, the sister of the Marquis of Tuscany,
a princess of German origin, of great wealth, a subject and a relative of the Emperor himself.
Trusting in this great alliance, Pietro no longer concealed the designs he entertained for himself and his family, branches of which were established in Padua and Vicenza, where they enjoyed, and certainly exacted, the highest consideration. Indeed, most of the Candiano men seem to have married women allied to reigning princes.
The Doge, their head, now garrisoned with German soldiers a number of fortresses in the neighbourhood of Ferrara, which had come to him with his wife; lastly, he did what every tyrant has done since history began, he surrounded himself with a mercenary bodyguard of desperate men who had everything to gain by his success, and everything to lose if he fell. After this he showed plainly enough that he meant to emancipate himself altogether from those counsellors which the Republic imposed upon him in all the important affairs of state.
He might have succeeded in any other state, but in Venice his was not the only family that aspired to the supreme power. His deeds had been violent, high-handed, outrageous, such as would condemn the chief of any community that called itself free; the Orseolo watched him, lay in wait for him, trapped him, and compassed his end. Following their lead, the people formed themselves into a vast conspiracy, and at a signal the ducal palace was surrounded on all sides.