After the legion was withdrawn in c. AD 49, the legionary defences were dismantled and the fortress converted into a town, with many of the barrack blocks converted into housing. Its official name became "Colonia Victricensis", with discharged Roman soldiers making up the population; a bronze military "diplomata" (document formalising a soldier's retirement, citizen rights and land rights) for a legionary soldier called "Saturninus" has been found at the Sheepen site. As a colonia (the only one in Britain at the time) its citizens held equal rights to Romans, and it was the principal city of Roman Britain. Tacitus wrote that the town was "a strong "colonia" of ex-soldiers established on conquered territory, to provide a protection against rebels and a centre for instructing the provincials in the procedures of the law". The Temple of Claudius, the largest classical style temple in Britain, was built there in the 50s and was dedicated to Emperor Claudius on his death in 54. The podium, or foundation of the temple, was incorporated into the Norman castle, and represents "the earliest substantial stone building of Roman date visible in the country". A monumental arch was built from tufa and Purbeck Marble at the western gate out of the town. Tombs lined the roads out of the town, with several belonging to military veterans giving insights into the military units stationed in Britain during the post-Conquest period, such as: