Ivan Crnojević became ruler of Zeta in 1465. His rule lasted until 1490. Immediately after taking the throne, Ivan attacked Venice, breaking the alliance his father had forged. He fought Venice in an attempt to capture Kotor. He had some success, gaining increasing support from the coastal Slavic tribes of Grbalj and Paštrovići in his quest to assert control over the Bay of Kotor. But when the Ottoman campaign in northern Albania and Bosnia convinced him that the main source of danger to his country was to the East, he sought a compromise with Venice. Ivan fought numerous battles against the Turks.

Zeta and Venice fought against the Ottoman Empire. The war ended with the successful defense of Shkodra, where Venetian, Shkodran, and Zetan defenders fought off forces of against Turkish Sultan Mehmed II and eventually won the war in 1474. However, the Ottomans besieged Shkodra again in 1478, with Mehmed II coming personally to lead that siege. After the Ottomans failed to take Shkodra by direct force, they assaulted Žabljak and took it without resistance. Venice ceded Shkodra to the sultan in 1479 in Treaty of Constantinople. Ivan had aspirations to organise an anti-Turkish alliance consisting of Napolitan, Venetian, Hungarian, and Zetan forces. However, his dream could not be fulfilled since the Venetians did not dare to help Ivan after their peace treaty with the Ottoman Empire in 1479. Left on his own, Ivan managed to preserve Zeta from frequent Ottoman offensives.

Knowing that the Ottomans would try to punish him for fighting on the Venetian side, and in order to preserve his independence, in 1482 he moved his capital from Žabljak on Lake Skadar to the mountainous area of Dolac, under Mount Lovćen. There he built the Orthodox Cetinje Monastery, around which the capital, Cetinje, would emerge. In 1496, Ottomans conquered Zeta and consolidated it into the newly established Sanjak of Montenegro, thereby ending its principality.