Maxima Caesariensis was the name of one of the four provinces of Roman Britain, as named in the Verona List , dated AD 312 - 314.

Its capital was Londinium and probably encompassed what is now south east England.

Originally its governors were of equestrian rank but by the mid fourth century they had to be of consular rank.

Maxima Caesariensis and its northern neighbour, Flavia Caesariensis, may have briefly comprised a single province which covered most of what is now eastern England. Eric Birley and others have suggested that the two provinces named Caesariensis were descended from a larger unit which received its unusual name due to Imperial favour. After London welcomed Constantius Chlorus in 296 he argues that [he may have granted it the additional title of 'Caesariensis'. Given the circumstances at the time Constantius may well have divided the military command of Britannia Superior in two with an eastern province named Britannia Caesariensis and a western one named Britannia Prima. This division would have been later reorganised by splitting Britannia Caesariensis into north and south regions named after Constantius and the western Augustus, Marcus Aurelius Valerius Maximianus This would require the split to have taken place prior to Maximian's abdication in 305. As Constantius was elevated to the title of Augustus in the same year, London may also have adopted the title at the same time, as indeed it was later known. The short period of it holding the title Caesariensis may explain why there is little other evidence of that name.

An alternative explanation is that the province was named after Galarius Maximianus , emperor of the east. This raises the question of why an eastern emperor was honoured and the two Augusti of the Tetrachy were not however.