Cohors Primae Ubiorum

Cohors I Ubiorum was a Roman auxiliary cohort. The cohort was at one point or another stationed at Calidava/Calidaua (modern day Capidava in Romania). The Cohors I Ubiorum was likely created during the reign of Augustus, and it is known to have been in existence during the reign of Domitian in the late 1st century AD. The unit likely played a role in maintaining Roman control over the area and in defending the Roman frontier against incursions by Germanic tribes. The cohort likely played a role in maintaining Roman control over the region.

We only learn about this department, which apparently only existed for a few months, through Tacitus. He tells Agr. 28, that in the summer of 83 she was to be transferred to Britain from Germania, where she had been newly formed, but that on the way the recruits revolted, slaughtered the officer in command of them and the old enlisted men and fled on the transport ships; He then reports in detail their further fates. The same story is completely distorted and without the name of the cohort Dio LXVI 20, 2.

The same summer a Usipian cohort, which had been levied in Germany and transported into Britain, ventured on a great and memorable exploit. Having killed a centurion and some soldiers, who, to impart military discipline, had been incorporated with their ranks and were employed at once to instruct and command them, they embarked on board three swift galleys with pilots pressed into their service.  Under the direction of one of them—for two of the three they suspected and consequently put to death—they sailed past the coast in the strangest way before any rumour about them was in circulation. After a while, dispersing in search of water and provisions, they encountered many of the Britons, who sought to defend their property. Often victorious though now and then beaten, they were at last reduced to such an extremity of want as to be compelled to eat, at first, the feeblest of their number, and then victims selected by lot. Having sailed round Britain and lost their vessels from not knowing how to manage them, they were looked upon as pirates and were intercepted, first by the Suevi and then by the Frisii. Some who were sold as slaves in the way of trade, and were brought through the process of barter as far as our side of the Rhine, gained notoriety by the disclosure of this extraordinary adventure.Gaius Cornelius Tacitus – The Agricola