In 1997 Gloucester celebrated its foundation as a Roman colonia. This was a civil settlement for retired Roman legionaries, and carried with it the status of Rome itself. It was the third of only four coloniae in Britain, and was therefore one of the most important cities of the Roman province - indeed, it may have become a provincial capital later.
We know Gloucester as Col. Ner. Glev. from inscriptions which has been understood to mean Colonia Nerviana (or Nerviae) Glevensis (or Glevensium), literally the colony of Nervian Gloucester, or the colony of the Gloucestrians of Nerva (although other expansions have been suggested) - the key is the link to Nerva.
In any event, this has given us a date for the creation - or at least the naming - of the colony. It must have been between late 96, and early 98 when Nerva enjoyed his short reign. At least one school of thought suggests that the colony was founded under Domitian but this remains to be proven, as his name was erased from all monuments (in theory) after his death. It is unlikely that any colony bearing his name would have retained it, so it is possible that Glevum renamed itself for the new emperor.
The date of 97 is a 'best guess', so after the 1997 celebrationsGloucester Civic Trust commissioned the sculptor Anthony Stone to design a commemorative statue to also celebrate the Millennium. Remains of a Roman equestrian statue had been found in 1968 under the modern Eastgate Shopping Centre. This discovery provided the inspiration, as it had probably been a statue of an emperor - not necessarily Nerva.
A long campaign of fund-raising was begun, culminating in the erection of the statue in 2002.