The Second Crusade (1147–1148) offered Roger an opportunity to revive attacks on the Byzantine Empire, the traditional Norman enemy to the East. It also afforded him an opportunity, through the agency of Theodwin, a cardinal ever-vigilant for Crusade supporters, to strike up a correspondence with Conrad III of Germany in an effort to break his alliance with Manuel I Comnenus. Roger himself never went on an expedition against Byzantium, instead handing command to the skillful George. In 1147, George set sail from Otranto with seventy galleys to attack Corfu. According to Nicetas Choniates, the island capitulated thanks to George's bribes (and the tax burden of the imperial government), welcoming the Normans as their liberators. Leaving a garrison of 1,000 men, George sailed on to the Peloponnesus. He sacked Athens and quickly moved on to the Aegean Islands. He ravaged the coast all along Euboea and the Gulf of Corinth and penetrated as far as Thebes, Greece, where he pillaged the silk factories and carried off the Jewish damask, brocade, and silk weavers, taking them back to Palermo where they formed the basis for the Sicilian silk industry. George capped the expedition with a sack of Corinth, in which the relics of Saint Theodore were stolen, and then returned to Sicily. In 1149, however, Corfu was retaken. George went on a punitive expedition against Constantinople, but could not land and instead defied the Byzantine emperor by firing arrows against the palace windows. Despite this act, his expedition left no enduring effects.