Gothic groups began launching larger raids across the Lower Danube into Roman Moesia in the mid-3rd century. A raid in 238 is linked in ancient accounts to violence at Histria and to Roman responses that included payments and prisoner returns. These early incursions set a pattern of frontier pressure, bargaining, and repeated conflict.
In 248, renewed raids by Goths and the Carpi struck the Lower Danube provinces after disputes over Roman subsidies and payments. The violence exposed how dependent the frontier could become on negotiated payments and how quickly raids returned when those arrangements broke down. The fighting helped pull the Danubian army and commanders further into imperial politics.
Around 250–251, Gothic forces under Cniva pushed deep into Thrace and besieged Philippopolis (modern Plovdiv). After a long siege, the city fell, demonstrating that Gothic groups could threaten major Balkan centers, not just frontier forts. The disaster sharpened Rome’s urgency to confront raiders before they could withdraw north with plunder.
In summer 251, Emperor Decius met Cniva’s coalition near Abritus in Moesia Inferior. The Roman army was defeated, and Decius and his son Herennius Etruscus were killed—an exceptional shock for Roman prestige and stability. The outcome encouraged further pressure on the Lower Danube frontier and highlighted the empire’s wider mid-3rd-century crisis.
In 267–269, large raiding coalitions—often labeled “Scythians” in ancient sources and including groups such as the Heruli—struck the Balkans and Greece. Athens was sacked in 267, showing how raids connected the Danube frontier to wider routes across the Black Sea and Aegean. These attacks prompted major Roman field operations to restore control.
In 269, Emperor Claudius II won a major victory over Gothic invaders near Naissus (modern Niš). The battle helped stabilize the Balkans after years of heavy raiding. Claudius’ reputation from this victory shaped later Roman expectations that strong field armies could still deter large Gothic movements.
By 274, Emperor Aurelian decided to abandon Roman Dacia north of the Danube and resettle troops and civilians south of the river. This policy change made the Lower Danube an even more central boundary between Roman provinces and Gothic-ruled territories beyond. It also framed later interactions as a frontier system of forts, diplomacy, and managed crossings.
In the early 4th century, fighting along the Lower Danube culminated in a treaty associated with Constantine and the Goths in 332. The agreement is widely understood as restoring Roman influence by setting terms for peace, trade, and Gothic obligations such as supplying troops. It marked a shift toward managing Gothic power through formal frontier diplomacy rather than only through punitive raids.
From 367 to 369, Emperor Valens led repeated operations against the Tervingi, a Gothic group based north of the Lower Danube. The campaigns combined battlefield action with pressure on frontier trade, which mattered for Gothic economies tied to Roman goods. The fighting ended with a treaty in 369, but the settlement reduced earlier privileges and left relations strained.
In 376, large numbers of Tervingi Goths asked to cross the Danube into Roman territory, driven by pressure from forces advancing into the steppe (including the Huns). Roman authorities permitted the crossing and directed settlement in the Diocese of Thrace, but the movement strained transport and food supplies. Mismanagement and abuses by local officials helped turn a controlled resettlement into a destabilizing crisis.
Later in 376, tensions around the new Gothic settlers escalated into open conflict near Marcianople. A failed attempt to control or eliminate Gothic leadership and a subsequent clash with Roman troops helped trigger a wider war in the Balkans. The fighting showed how quickly settlement policy could collapse into violence when food, security, and trust broke down.
In 378, Emperor Valens fought the Goths near Adrianople and suffered a catastrophic defeat, with Valens killed in the battle. The loss weakened Roman military capacity in the Balkans and changed negotiations with Gothic leaders. It also made clear that large Gothic groups inside imperial territory could no longer be treated as a short-term refugee problem.
In 382, Emperor Theodosius I reached an agreement that ended major fighting and settled at least some Goths within the empire, likely in parts of Lower Moesia and the Diocese of Thrace. In broad terms, the settlement exchanged land and a place inside the imperial system for military service. This created a long-lasting model of Gothic communities living on or near the Lower Danube as foederati (allied groups tied to Rome by agreement).
Gothic incursions and settlements on the Lower Danube (3rd–4th centuries CE)