a particularly warlike tribe, the Senones, invaded two Etruscan towns close to Rome's sphere of influence. These towns, overwhelmed by the enemy's numbers and ferocity, called on Rome for help. The Romans met the Gauls in pitched battle at the Battle of Allia River around 390–387 BC. The Gauls, led by the chieftain Brennus, defeated the Roman army of approximately 15,000 troops, pursued the fleeing Romans back to Rome, and sacked the city before being either driven off or bought off. Roman expansion in Italy Wars against Italian neighbours From 343 to 341, Rome won two battles against their Samnite neighbours, but were unable to consolidate their gains, due to the outbreak of war with former Latin allies. In the Latin War (340–338), Rome defeated a coalition of Latins at the battles of Vesuvius and the Trifanum. The Latins submitted to Roman rule. A Second Samnite War began in 327. The fortunes of the two sides fluctuated, but from 314, Rome was dominant, and offered progressively unfavourable terms for peace. The war ended with Samnite defeat at the Battle of Bovianum (305). By the following year, Rome had annexed most Samnite territory and began to establish colonies there; but in 298 the Samnites rebelled, and defeated a Roman army, in a Third Samnite War. Following this success they built a coalition of several previous enemies of Rome. However, the war eventually ended with a Roman victory in 290. At the Battle of Populonia, in 282, Rome finished off the last vestiges of Etruscan power in the region. Rise of the plebeian nobility In the 4th century, plebeians gradually obtained political equality with patricians. The starting point was in 400, when the first plebeian consular tribunes were elected; likewise, several subsequent consular colleges counted plebeians (in 399, 396, 388, 383, and 379). The reason behind this sudden gain is unknown, but it was limited as patrician tribunes retained preeminence over their plebeian colleagues. In 385, the former consul and saviour of the besieged Capitol Marcus Manlius Capitolinus is said to have sided with the plebeians, ruined by the sack and largely indebted to patricians. Livy tells that Capitolinus sold his estate to repay the debt of many of them, and even went over to the plebs, the first patrician to do so. Nevertheless, the growing unrest he had caused led to his trial for seeking kingly power; he was consequently sentenced