Shortly after the start of the Second Punic War, Hannibal crossed into Italy by traversing the Pyrenees and the Alps during the summer and early autumn of 218 BC. He quickly won major victories over the Romans at Trebia and at Lake Trasimene. After these losses, the Romans appointed Quintus Fabius Maximus Verrucosus as dictator to deal with the threat. Fabius used attrition warfare against Hannibal, cutting off his supply lines and avoiding pitched battles. These tactics proved unpopular with the Romans who, as they recovered from the shock of Hannibal's victories, began to question the wisdom of the Fabian strategy, which had given the Carthaginian army a chance to regroup. The majority of Romans were eager to see a quick conclusion to the war. It was feared that, if Hannibal continued plundering Italy unopposed, Rome's allies might defect to the Carthaginian side for self-preservation.