Between July 960 and March 961 Nikephoros Phokas besieged Chandax through a Cretan winter and took it, ending 135 years of Muslim rule on Crete and the piracy that had made the Aegean unsafe.
In July 960 a Byzantine expedition landed on Crete under Nikephoros Phokas, Domestic of the Schools, and settled down in front of the emirate's capital at Chandax. It stayed through the autumn, through a winter on a hostile island, and stormed the city on 6 March 961.
The island had been Muslim for a hundred and thirty-five years and the base from which Aegean piracy operated. Four earlier expeditions — in 843, 866, 911 and 949 — had all been sent to take it back, and all four had failed.
The difference in 961 was not tactical brilliance but persistence and logistics: an army that could be supplied by sea and a commander who refused to sail home for the winter. Nikephoros was proclaimed emperor two years later, and the fleet and treasury that Crete freed up paid for the conquests of Cilicia, Cyprus and Antioch that followed.
Crete had been taken in the 820s by Andalusian exiles and turned into a corsair state whose fleets raided the islands, the Greek coasts and shipping across the eastern Mediterranean. For the empire it was not a border problem but an interior one: the Aegean is the sea Constantinople sits on.
The record of failure was long and expensive. An expedition in 843 collapsed; the one prepared in 866 ended before it sailed when its commander, the Caesar Bardas, was murdered in the camp; a large fleet under Himerios was destroyed in 911; another attempt in 949 was beaten on the beaches.
By 960 the empire was in a stronger position than at any point since the Arab conquests. The eastern frontier had been reversed since the Lalakaon, the Abbasid caliphate had fragmented, and Constantinople had a professional army and the ships to move it.
The expedition sailed in the summer of 960 and made an opposed landing on the north coast. Byzantine accounts describe purpose-built transports that let armoured cavalry come ashore ready to fight rather than assembling on the beach under attack, which is the moment amphibious operations of this period usually failed.
The Cretan force that met the landing was beaten, and the army moved on Chandax — al-Khandaq, "the ditch", the fortified capital the emirate had built when it took the island.
Nikephoros then made the decision the campaign turned on. Rather than raid the island and withdraw before winter, as every previous expedition had done, he invested the city and prepared to stay.
The siege ran for eight months. The city was strongly walled and well provisioned, no relief came from Egypt or Syria, and the besiegers spent the winter in camp on an island whose countryside was hostile.
The fleet is what made it possible: it kept the army fed, blockaded the harbour, and prevented the emirate from doing what it had always done and dispersing its ships to raid elsewhere.
By late winter the Byzantines were mining under the walls. On 6 March 961 a section was brought down and the city was stormed and sacked. The emir Abd al-Aziz was captured, and the plunder of a century of piracy went back to Constantinople with the army.
Crete became Byzantine territory again and was resettled and Christianised over the following decades, a process the monk Nikon led with a preaching mission remembered for the single word he was named after.
The strategic effect was immediate. The Aegean stopped being a raiding ground, the islands and the Greek coasts became safe for the first time in generations, and the fleet that had been tied to defending them was freed for offensive use in the east.
Nikephoros celebrated a triumph in Constantinople, was sent east to campaign against Aleppo the following year, and was proclaimed emperor in 963 by an army that had followed him to Crete. The captured emir's son entered Byzantine service and died fighting for the empire at Dorostolon.
Chandax is where the Byzantine recovery becomes a reconquest. The Lalakaon in 863 had ended the raids the empire suffered; 961 took territory back, and it took the one piece of territory whose loss had been felt in every port in the Aegean.
It also made a dynasty. The Phokas family had produced generals for generations, and the prestige of Crete carried Nikephoros to the throne — the second time in the archive that a successful frontier commander becomes emperor, after Leo III.
And it set the pattern for the next decade: an amphibious, well-supplied, patient campaign against a fragmented Muslim world, which is what took Cilicia and Cyprus in 964–965 and Antioch in 969.