Laeti

Laeti /ˈlɛtaɪ/, the plural form of laetus /ˈliːtəs/, was a term used in the late Roman Empire to denote communities of barbari ("barbarians") i.e. foreigners, or people from outside the Empire, permitted to settle on, and granted land in, imperial territory on condition that they provide recruits for the Roman military. The term laetus is of uncertain origin. It means "lucky" or "happy" in Latin but may derive from a non-Latin word. It may derive from a Germanic word meaning "serf" or "half-free colonist". Other authorities suggest the term was of Celtic or Iranian origin.

Laeti may have been groups of migrants drawn from the tribes that lived beyond the Empire's borders. These had been in constant contact and intermittent warfare with the Empire since its northern borders were stabilized in the reign of Augustus in the early 1st century. In the West, these tribes were primarily Germans, living beyond the Rhine. There is no mention in the sources of laeti in the Eastern section of the Empire. Literary sources mention laeti only from the late 3rd and 4th centuries.

Although the literary sources mention laeti only from the 4th century onwards, it is likely that their antecedents existed from as early as the 2nd century: the 3rd-century historian Dio Cassius reports that emperor Marcus Aurelius (ruled 161–180) granted land in the border regions of Germania, Pannonia, Moesia and Dacia, and even in Italy itself, to groups of Marcomanni, Quadi and Iazyges tribespeople captured during the Marcomannic Wars (although Marcus Aurelius later expelled those settled in the peninsula after one group mutinied and briefly seized Ravenna, the base of the Adriatic fleet). These settlers may have been the original laeti. Indeed, there is evidence that the practice of settling communities of barbari inside the Empire stretches as far back as the founder-emperor Augustus himself (ruled 42 BC - 14 AD): during his time, a number of subgroups of German tribes from the eastern bank of the Rhine were transferred, at their own request, to the Roman-controlled western bank, e.g. the Cugerni, a subgroup of the Sugambri tribe, and the Ubii. In 69, the emperor Otho is reported to have settled communities of Mauri from North Africa in the province of Hispania Baetica (modern Andalusia, Spain). Given the attestation of several auxiliary regiments with the names of these tribes in the 1st and 2nd centuries, it is likely that their admission to the empire was conditional on some kind of military obligations (Tacitus states that the Ubii were given the task of guarding the West bank of the Rhine) i.e. that they were laeti in all but name.

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