During the second half of the 19th century, the fortress began to lose its usefulness, due to many developments in military technology. Former bastions and military spaces were demolished and replaced with new boulevards and neighbourhoods. The first identifiable civilisation in Banat were the Dacians who left traces of their past. Although its location is unknown, the coordinates given by geographer Ptolemy in Geographike Hyphegesis place it in the northwest of Banat.
It is assumed that in the 9th century Knyaz Glad ruled over these lands, accepting Hungarian sovereignty, though no contemporary accounts exist. The palace was built by Italian craftsmen and was organised around a rectangular court having a main body provided with a dungeon or a tower.
On 10 August he tried to change the course of Bega River to be able to enter more easily into the city, but he was defeated by attacks from both inside and outside the city. After a failed siege in , the Turks regrouped and returned with a new strategy. Except for a period in the late 16th century, the city did not suffer sieges until the end of the 17th century.
After 40 days of futile efforts, the besiegers drew back. The Ottoman military, the kuruc and the Turkish civilian population were forced to leave the city after a day siege marked by repeated bombings that destroyed much of the city's buildings. The existing fortifications could not cope with the new military techniques, so the entire fortress was rebuilt in a late, flat and inconsistent adaptation of the Vauban style.
It had an area 10 times larger than the medieval Turkish fortress. Between and , Bega River was regulated, creating a navigable canal. Under the political pressure of the Hungarian Diet , the Viennese Imperial Court accepted that the three counties of Banat to be reincorporated into the Hungarian Kingdom, in The city was under siege in for days.
