This is a partial list of governors of Roman Britain from 43 to 409. As the unified province "Britannia", Roman Britain was a consular province, meaning that its governors had to first serve as a consul in Rome before they could govern it. While this rank could be obtained either as a suffect or ordinarius, a number of governors were consules ordinarii, and also appear in the List of Early Imperial Roman Consuls. After Roman Britain was divided, first into two (early 3rd century), then into four (293), later governors could be of the lower, equestrian rank.
Not all the governors are recorded by Roman historians and many listed here are derived from epigraphic evidence or from sources such as the Vindolanda letters. Beyond the recall of Gnaeus Julius Agricola in 85 the dates of service of those who can be named can only be inferred. Others are still entirely anonymous and by the time of the division of Britain into separate provinces, the record is very patchy.
Some sources list a further governor, a second Ulpius Marcellus. He was interpreted as a son of the first Ulpius Marcellus, serving. c. 211. This is based on a misdated inscription and it is now accepted that it refers to the earlier Ulpius Marcellus only.
The two sons of emperor Septimius Severus, Caracalla and Publius Septimius Geta, administered the province to some degree during and immediately after their father's campaigns there which took place between 208 and 211.
This list assumes the final division occurred c. 213.
Following the reabsorption of Britain into the Roman Empire, the island was further repartitioned by Diocletian, this time into four separate provinces, Maxima Caesariensis in the southeast, with its capital at London, Flavia Caesariensis in the east, with its capital at Lincoln, Britannia Secunda in the north, with its capital at York, and Britannia Prima in the west (including present day Wales), with its capital at Cirencester. A fifth province called Valentia also briefly existed, probably in the far north. Each had a governor of equestrian rank (a praeses) and they were overseen by a vicarius. Later in the 4th century, the governor of Maxima Caesariensis had to be of consular rank. The following names are the few which have survived from this era, covering the almost 100 years until c. 408, when the Roman civilian administration was expelled by the native population.[citation needed]