Quadi in the context of "Marcomanni"

The Suebi (also spelled Suevi or Suavi) were a large group of Germanic peoples first reported by Julius Caesar in the 1st century BC. In different contexts over several centuries, peoples within this umbrella category were sometimes simply called the Suebi, although all or most Suebian peoples had their own names as well. They originated near the Elbe River in what is now Eastern Germany. From there, Suebian groups spread across Central Europe, and in the 5th and 6th centuries some took over parts of Spain, Portugal and Italy. Archaeologically, the forerunners of the Suebi before contact with Rome are associated with the Jastorf culture. During the Roman imperial period the Suebi are associated with the so-called "Elbe Germanic peoples" who brought Elbe material culture into new areas to the south and southwest. Linguistically, although contemporary evidence for Roman-era Suebian language is scarce, they spoke a Germanic language, which is believed to be the main predecessor of medieval Old High German, and the modern German language, with all its related dialects.

With the advent of Roman dominance in the 1st and 2nd centuries AD, some Suebi moved into Roman controlled regions near the Neckar river, while a powerful Suebian alliance outside their control maintained a tense relationship with the Roman empire. This was led by the Marcomanni, who settled with other Suebi in remote forests and mountains north of the Roman border along the Danube river, and maintained connections with Suebian and non-Suebian peoples to their north. After their crushing defeat to the Romans in the Marcomannic Wars of the late 2nd century, many Suebi moved into the Roman Empire, or regrouped in areas near the Roman frontier. Notably, the diverse group who came to be known as the Alemanni, took control of Roman territory in what later became medieval Swabia - a cultural region in southern Germany that still bears a version of the Suebian name. During the 3rd and 4th centuries, the Romans were often raided by the Alemanni, Juthungi, Quadi and other Suebi, and attempts to subjugate them had limited success.

A client kingdom or people in ancient Rome meant a kingdom or ancient people that was in the condition of "appearing" still independent, but in the "sphere of influence" and thus dependence of the neighboring Roman Empire. It was a form of modern protectorate, where the kingdom or territory in question was controlled (protected) by a stronger one (protector).

The barbarian invasions of the third century (212–305) constituted an uninterrupted period of raids within the borders of the Roman Empire, conducted for purposes of plunder and booty by armed peoples belonging to populations gravitating along the northern frontiers: Picts, Caledonians, and Saxons in Britain; the Germanic tribes of Frisii, Saxons, Franks, Alemanni, Burgundians, Marcomanni, Quadi, Lugii, Vandals, Juthungi, Gepids and Goths (Tervingi in the west and Greuthungi in the east), the Dacian tribes of the Carpi and the Sarmatian tribes of Iazyges, Roxolani and Alans, as well as Bastarnae, Scythians, Borani and Heruli along the Rhine-Danube rivers and the Black Sea.

Since the time of Marcus Aurelius during the Marcomannic Wars (166/167-189), Germanic-Sarmatian tribes had not exerted such strong pressure along the northern borders of the Roman Empire.

Valentinian I (Latin: Valentinianus; 321 – 17 November 375), sometimes known as Valentinian the Great, was Roman emperor from 364 to 375. He ruled the Western half of the empire, while his brother Valens ruled the East. During his reign, he fought successfully against the Alamanni, Quadi, and Sarmatians, strengthening the border fortifications and conducting campaigns across the Rhine and Danube. Also, his general Theodosius the Elder defeated a revolt in Africa and the Great Conspiracy (a coordinated assault on Roman Britain by Picts, Scoti, and Saxons). Valentinian founded the Valentinian dynasty, with his sons Gratian and Valentinian II succeeding him in the western half of the empire and his daughter Galla marrying emperor Theodosius I.

The Marcomannic Wars (Latin: bellum Germanicum et Sarmaticum, lit. 'German and Sarmatian war') were a series of wars lasting from about AD 166 until 180. These wars pitted the Roman Empire against principally the Germanic Marcomanni and Quadi and the Sarmatian Iazyges; there were related conflicts with several other Germanic, Sarmatian, and Gothic peoples along both sides of the whole length of the Roman Empire's northeastern European border, the river Danube.

The struggle against the Germans and Sarmatians occupied the major part of the reign of Roman emperor Marcus Aurelius, and it was during his campaigns against them that he started writing his philosophical work Meditations.

Furtius (flourished in 2nd century AD) was a ruler of the Quadi, a Germanic tribe, during the Marcomannic War.

Furtius is mentioned in the Historia romana of Cassius Dio. He had negotiated a peace treaty with Roman Emperor Marcus Aurelius. Since he considered the Quadi untrustworthy and because they were not fulfilling the conditions of the treaty, in particular with respect to the return of Roman prisoners of war, Marcus decided to invade the Quadi and destroy them completely. At this point the Quadi deposed Furtius and replaced him with Ariogaesus.