Until the sixteenth century, the struggle against the Ottomans was fought in the hinterland of Dalmatia. Croatian cities bravely guarded the road to the Dalmatian communes, but with the fall of Knin, Skradin and finally Klis in 1537 into Ottoman hands, the Venetians realized that they now depend on themselves. They are starting a project to establish the capital, strategically important city of Dalmatia, Zadar. In parallel with the arrangement of the bastion system in Zadar, according to the new principles of construction, proposals are made to protect other cities. However, due to the unfavorable position of Šibenik, Trogir and Split, only the construction of the fortress of St. Nikola in order to prevent the enemy from approaching Šibenik from the sea. In order to reduce costs, Venice introduced a system of territorial armies composed of the local population in Dalmatia. It had an obligation to serve in the territorial army, cernida. With the improvement of firearms, there are changes in the way of warfare. Troops are sheltering inside the walls, and light cavalry and artillery are increasingly being used in battles. In addition to the system of territorial army that developed in the 16th century, there was the development of military entrepreneurship in Dalmatia. The Venetians call the infantry and cavalry units coming from Dalmatia the Oltramarini. Under this name, they unite the elite cavalry, infantry and naval units Croati a cavallo, Soldati Albanesi and Barche armate croate composed of Croats and Albanians, who participate in the defense of Dalmatia but also in the wars in the terrafer. Dalmatia was a minor battlefield for Venice in the 16th century, focusing mostly on the fortification of Zadar, while by forming territorial military units it sought to save, and by recruiting domestic professional units to obtain a reliable army.