It is presumed that the Aventine was state-owned public land; in c.456 BC a Lex Icilia allowed or granted the plebs property rights there. By c.391 BC, the city's overspill had overtaken the Aventine and the Campus Martius, and left the city vulnerable to attack; around that year, the Gauls overran and temporarily held the city. After this, the walls were rebuilt or extended to properly incorporate the Aventine; this is more or less coincident with the increasing power and influence of the Aventine-based plebeian aediles and tribunes in Roman public affairs, and the rise of a plebeian nobility.[12]