The town is mentioned in the Turkish chronicles in connection with the political and military events from the south or the nord of Danube. So, in 1331, the Arabian geographer Abulfeda, mentions Isaccea as “a town in Wallachians’ country”, named Isakdji. Subsequently the name is mentioned in different alternatives: Isaac, Isaccea or the Russian name Obluciţa.

Due to the proximity of Danube, Isaccea represents a real hearth of history. Archaeological investigations revealed the existence of a Neolithic settlement 7000 years old at the north-western extremity of the locality. Most likely that through Isaccea ford Darius, the Persian king, passed his troops across Istru river in the expedition against Scythians; still in this place, on a sailing ship in the river’s offing, in 369 A.D., the Roman emperor Valens and Visigothic leader Athanaric concluded a peace treaty. The fact that the vestiges from the Roman period, Roman-Byzantine period and Early Middle Age are the most relevant is not accidentally.

Noviodunum citadel, which ruins are at 2 km east from the actual town, elevated on a promontory over 20 m high, at the point “Pontonul vechi” or “Eski-Kale” (in Turkish “The old Fortress”), has a special importance. It was built in the first years of the Principality on an old Getic settlement. It has a military, strategic and economic role, being situated at the crossing point of important thoroughfares and at the most important ford of Danube, at the same time constituting the main station of the Roman fleet (Classis Flavia Moesica) and headquarters of some detachments of the legions camped in Dobrudja. Its importance and also the importance of the civil settlement developed around the citadel led to grant of municipium status at the time of Severs. Destroyed by the barbarians in 267 and rebuilt by the Roman emperors Aurelian and Probus, the fortress will consolidate its strategic and economic position in the Roman-Byzantine period. Archaeological testimonies prove that the settlement was one the most powerful Palaeo-Christian centres from Low Danube.

For over two centuries (beginning of VII – third quarter of X) the urbane life declines. At the end of X century and the beginning of XI, the fortress resumes its defensive function the precinct being remade by the Byzantines on the old Roman-Byzantine foundations.

Conquered by the Tartars, then ruled for a period by Mircea the Old, after being conquered by the Turks, in 1420, the fortress walls have been destroyed. In the XVI century, up on the fortress, the Turks built a trapezoidal camp surrounded by a precinct earthwork wall which protected a garrison. Simultaneously, as early as the XIII century, the core of the settlement has moved to the south, where a settlement named Isakdji has been founded. The name was taken from the old citadel civil settlement.

Under the Ottoman domination (XV-XIX), Isaccea was an important administrative, military and economic centre. After the Independence War (1877-1878) the town is integrated into Romania.

After 1928, Isaccea becomes town subordinated to the County’s residence, Tulcea