The coalition's main chance came in 62 BC, when the Greek cities rebelled against Roman rule. In 61 BC, the notoriously oppressive and militarily incompetent proconsul of Macedonia, Gaius Antonius, nicknamed "Hybrida" ("The Monster"), an uncle of the famous Mark Antony, led an army against the Greek cities. As his army approached Histria, Antonius detached his entire mounted force from the marching column and led it away on a lengthy excursion, leaving his infantry without cavalry cover, a tactic he had already used with disastrous results against the Dardani. Dio implies that he did so out of cowardice, in order to avoid the imminent clash with the opposition, but it is more likely that he was pursuing a large enemy cavalry force, probably Sarmatians. A Bastarnae host, which had crossed the Danube to assist the Histrians, promptly attacked, surrounded and massacred the Roman infantry, capturing several of their "vexilla" (military standards). This battle resulted in the collapse of the Roman position on the lower Danube. Burebista apparently annexed the Greek cities (55–48 BC). At the same time, the subjugated "allied" tribes of Moesia and Thrace evidently repudiated their treaties with Rome, as they had to be reconquered by Augustus in 29–8 BC (see below).