With few troops left in Britain, many Romano-British towns—including Londinium—declined drastically over the next few decades. Many of London's public buildings had fallen into disrepair by this point, and excavations of the port show signs of rapid disuse. Between 407 and 409, large numbers of barbarians overran Gaul and Hispania, seriously weakening communication between Rome and Britain. Trade broke down. Officials went unpaid and Romano-British troops elected their own leaders. Constantine III declared himself emperor over the west and crossed the Channel, an act considered the Roman withdrawal from Britain since the emperor Honorius subsequently directed the Britons to look to their own defence rather than send another garrison force. Surviving accounts are scanty and mixed with Welsh and Saxon legends concerning Vortigern, Hengest, Horsa, and Ambrosius Aurelianus. Even archaeological evidence of Londinium during this period is minimal.