It was Greek colonists who founded what became the thriving trading port of Mesembria in 512 BC, although most of their temples, gates and towers were submerged after the level of the Black Sea rose around 2000 years ago. To avoid the sorry fate of Apollonia (Sozopol), the populace of Mesembria accepted the Roman invaders in 72 BC, although the city’s status as a major trading centre gradually declined.
Under Byzantine rule from AD 395, Mesembria regained its former glory as a centre of commercial, strategic and religious importance, and during the 5th and 6th centuries, several grand churches were erected and the fortifications extended. After the Bulgar invasion in 812, the town was renamed Nesebâr; over the following centuries, it passed back and forth between Byzantium and the First Bulgarian Empire (681–1018), but remained largely unscathed. It was one of the last cities still under Byzantine stewardship when Constantinople fell in 1453; the Turks took Nesebâr the same year.
Under Ottoman rule, Nesebâr continued as the seat of a Greek bishop, and existing fortifications were strengthened to defend the city against pirates. During the Bulgarian National Revival of the 18th and 19th centuries, Nesebâr prospered, and wealthy merchants built grand villas here, some of which remain today. Overshadowed by Varna and later by Burgas, Nesebâr ceased to be an active trading town from the early 20th century, and these days survives almost entirely on tourism.