Leo of Tripoli was born in or near Attaleia, in modern-day Turkey. He was captured in a raid by Arabs and brought to Tripoli. While in captivity, he converted to Islam and began serving his captors in the capacity of a seaman. His name was changed to Arabic as Rashīq al-Wardāmī or Lāwī Abū’l-Hārit and given the title ghulām Zurāfa, meaning servant of Zurafa. Zurafa may have been his first Muslim master, but it is unknown.
Leo’s early life and career are unknown, but he apparently rose quickly through the ranks on the sea. The historian Mas’udi met him and described him as one of the best navigators of the time. Arabic sources list Leo as commander or admiral, as well as the governor of Tripoli and deputy-governor of Tarsus. Both Tripoli and Tarsus were important Muslim strategic centers as they were used to stage naval raids of the surrounding areas under the Abbasid Caliphate, which was fractured into autonomous dynasties at the time, with Baghdad as the capital.
During early 904 AD, Leo joined up with another Arab naval renegade, Damian of Tarsus, to participate in the successful campaign to take Egypt from the Tulunids. In Summer 904, Leo was heading an expedition of 54 vessels from the Syrian and Egyptian fleets, apparently to besiege the city of Constantinople – the capital of the Byzantine Empire. On the way, they successfully sacked Abydos, without a counterattack by the Byzantine military leader, Eustathios Argyros, who had the navy under his command. Since Argyros was reluctant to engage in conflict with the rebel Leo, the Byzantine Emperor, Leo VI, replaced him with admiral Himerios.
The rebel Leo thought it too risky to attack Constantinople directly, so he changed course and headed to Thessalonica – also under Byzantine control. The navy was unable to react quickly enough and Leo and his Saracen pirates engaged the city on July 29. After a short siege, the seaward walls were breached, being in a state of disrepair before the battle began. On July 31, Leo took the city and continued to sack it for a full week before departing back to their bases. Their booty consisted of 60 ships, 4,000 freed Muslim prisoners, a significant cache of loot and 22,000 captives. The chronicler, John Kaminiates, documented the siege and sacking of the city, and was among the many captives who were ransomed and exchanged for Muslim captives. It was one of the worst disasters of the 10th century for the Byzantines.
Leo the rebel continued raiding for years, defeating Himerios in April 912, with the assistance again from Damian of Tarsus, after being repelled while trying to take the Emirate of Crete. It wasn’t until 921-2 that the Byzantine navy, under John Rhadenos, was able to crush Leo and his fleet near Lemnos, destroying most of the ships. Leo narrowly escaped and disappeared from history afterwards.