In c. 44 BC, they moved into modern-day Hungary and Serbia near the Dacian steppe between the Danube and Tisza rivers, where they adopted a semi-sedentary lifestyle.
The united Scythians and Sarmatæ called themselves Iazyges, which Laurent connected with Old Church Slavonic ѩзꙑкъ (językŭ, "tongue, language, people").
[30] Before their migration into the Pannonian Basin, while still living north of Tyras, on the north-western coast of the Black Sea, the geographer Strabo states that their diet consisted largely of "honey, milk, and cheese".
These pottery workshops were built from the late 3rd century and have been found at Vršac–Crvenka, Grădinari–Selişte, Timişoara–Freidorf, Timişoara–Dragaşina, Hodoni, Pančevo, Dolovo, and Izvin şi Jabuca.
Finds of terra sigillata of an uncertain age have been found in Deta, Kovačica–Čapaš, Kuvin, Banatska Palanka, Pančevo, Vršac, Zrenjanin–Batka, Dolovo, Delibata, Perlez, Aradac, Botoš, and Bočar.
Finds of terra sigillata that have been confirmed to having been made the time of Iazygian possession but of uncertain date have been found in Timișoara–Cioreni, Hodoni, Iecea Mică, Timișoara–Freidorf, Satchinez, Criciova, Becicherecul Mic, and Foeni–Seliște.
[63][64] It is believed that a Roman road may have traversed the Iazyges' territory for about 200 miles (320 km),[65] connecting Aquincum to Porolissum, and passing near the site of modern-day Albertirsa.
[67] The area of plains between the Danube and Tisza rivers that was controlled by the Iazyges was similar in size to Italy and about 1,000 mi (1,600 km) long.
[70] In the 3rd century BC the Iazyges lived in modern-day south-eastern Ukraine along the northern shores of the Sea of Azov, which the Ancient Greeks and Romans called the Lake of Maeotis.
András Mócsy suggests that Gnaeus Cornelius Lentulus Augur, who was Roman consul in 26 BC, may have been responsible for the settlement of the Iazyges as a buffer between Pannonia and Dacia.
[79] Gheorghe Bichir and Ion Horațiu Crișan support the theory that the Iazyges first began to enter the Pannonian plain in large numbers under Tiberius, around 20 AD.
[80] The most prominent scholars that state the Iazyges were not brought in by the Romans, or later approved, are Doina Benea, Mark Ščukin, and Jenő Fitz.
Doina Benea states that the Iazyges slowly infiltrated the Pannonian plain sometime in the first half of the 1st century AD, without Roman involvement.
Andrea Vaday argued against the theory of a Roman approved or ordered migration, citing the lack of strategic reasoning, as the Dacians were not actively providing a threat to Rome during the 20–50 AD period.
Pliny's statements are corroborated by the earlier accounts of Seneca the Younger in his Quaestiones Naturales (61–64 AD), where he uses the Iazyges to discuss the borders that separate the various peoples.
After this, the Iazyges began to take possession of the Pannonian Basin, the land between the Danube and Tisa rivers in modern-day south-central Hungary.
[85][86][87][88][89][90] The Iazyges encountered the Basternae and Getae along their migration path sometime around 20 AD and turned southward to follow the coast of the Black Sea until they settled in the Danube Delta.
[91] Archeological finds suggest that while the Iazyges took hold of the northern plain between the Danube and the Tisa by around 50 AD, they did not take control of the land south of the Partiscum-Lugio line until the late 1st or early 2nd century.
[95] Around this time, some of the western parts of the land of the Iazyges were occupied, apparently without conflict, by the Quadi, which scholar Nicholas Higham states "suggests long-term collaboration between [them]".
[96][97] The client king was called socius et amicus Romani Populi (ally and friend of the Roman People); the exact obligations and rewards of this relationship, however, are vague.
[111] In early 92 AD the Iazyges, Roxolani, Dacians, and Suebi invaded the Roman province of Pannonia—modern-day Croatia, northern Serbia, and western Hungary.
[117] The threat presented by the Iazyges and neighbouring people to the Roman provinces was significant enough that Emperor Trajan travelled across the Mid and Lower Danube in late 98 to early 99, where he inspected existing fortification and initiated the construction of more forts and roads.
[111] Tacitus, a Roman Historian, records in his book Germania, which was written in 98 AD, that the Osi tribes paid tribute to both the Iazyges and the Quadi, although the exact date this relationship began is unknown.
[122][136][139] The exact terms of the peace treaty are not known, but it is believed the Romans kept Oltenia in exchange for some form of concession, likely involving a one-time tribute payment.
[144] Marcus Claudius Fronto, who was a general during the Parthian wars and then the governor of both Dacia and Upper Moesia, held them back for some time but was killed in battle in 170.
[158] Of the 8,000 auxiliaries, 5,500 of them were sent to Britannia[159] to serve with the Legio VI Victrix,[160] suggesting that the situation there was serious; it is likely the British tribes, seeing the Romans being preoccupied with war in Germania and Dacia, had decided to rebel.
[166] As part of a treaty made in 183, Commodus forbade the Quadi and the Marcomanni from waging war against the Iazyges, the Buri, or the Vandals, suggesting that at this time all three tribes were loyal client-tribes of Rome.
[197] Rome defended their Danubian border not just by way of repelling raids, but also by levying diplomatic influence against the tribes and launching punitive expeditions.
[200] Even after the Romans abandoned Dacia, they consistently projected their power north of the Danube against the Sarmatian tribes, especially during the reigns of Constantine, Constantius II, and Valentinian.
[201] To this end, Constantine constructed a permanent bridge across the middle Danube in order to improve logistics for campaigns against the Goths and Sarmatians.