Benedetto Zaccaria, and the White Salt That Made the Cloth
The first Genoese lords of Chios were a single family, and their route to the island ran through a substance that nobody has thought about for five hundred years and everybody in medieval Europe thought about constantly: alum.
Alum is potassium aluminium sulphate, a white crystalline salt, and it is a mordant. Without a mordant, dye does not fix to wool; it sits on the fibre and washes out. With alum, it bonds. The European textile industry was the largest manufacturing sector of the medieval West — the thing that made Flanders rich, that made Florence rich, that employed hundreds of thousands of people from England to Lombardy — and it could not operate without a reliable supply of alum. And in the thirteenth century the principal source in the Mediterranean world was the deposits around Phocaea, on the Anatolian coast just north of Smyrna, a few hours' sail from Chios.
In 1275 two Genoese brothers, Benedetto and Manuele Zaccaria, obtained the concession of Phocaea from the emperor Michael VIII, and Benedetto Zaccaria proceeded to become one of the most extraordinary men of the medieval Mediterranean.
He is difficult to describe briefly because he did too many things. He was an admiral — first for Genoa, then for Byzantium, then for the King of Castile, for whom he won a decisive action in the Strait of Gibraltar in 1291, and finally for Philip IV of France, who made him Admiral of France. He was a diplomat, and negotiated with the Ilkhans of Persia about a joint Mongol-Christian offensive against the Mamluks. He was, when required, a pirate. He founded a town in Spain. He commanded a crusading fleet.
And underneath all of it he was a businessman running an industrial monopoly. The Zaccaria alum operation was a genuinely modern-looking enterprise: extraction at Phocaea, processing, a dedicated fleet to carry the product, sales agents in the western markets, price management, and cartel agreements with competing producers to restrict output and hold prices up. He built a fortified town — New Phocaea — to house the operation. At its height, the Zaccaria controlled a large share of the alum reaching western Europe, and therefore held a hand on the throat of the cloth trade.
In 1304, Benedetto obtained Chios from the emperor Andronikos II, nominally as a ten-year concession, on the argument — which was perfectly true — that the island was exposed to Turkish raiding and the empire could not protect it. The rent was modest. The point was the mastic.
The Zaccaria held Chios for twenty-five years. Benedetto died in 1307, having done more in one lifetime than most dynasties manage in three, and the island passed to his successors: his son Paleologo, then Paleologo's nephews Martino and Benedetto II, who governed it increasingly as a family principality answerable to nobody.
Martino Zaccaria was the flamboyant one. He fought the Turkish corsairs of the Anatolian coast with genuine energy and considerable success, which earned him a reputation in the West as a bulwark of Christendom — and titles to match: the titular Latin emperor of Constantinople, Philip of Taranto, granted him the magnificent and entirely notional style of King and Despot of Asia Minor. He fortified the island heavily. He also stopped remitting anything meaningful to Constantinople and began behaving, in every practical sense, as an independent prince on Byzantine territory.
Andronikos III Palaiologos, who succeeded in 1328, was a considerably more energetic emperor than his grandfather. In 1329 he mounted a naval expedition against Chios with the assistance of Domenico Cattaneo, the Genoese lord of Phocaea and a rival of the Zaccaria. And the Greek population of the island, who had never been reconciled to Latin rule and had been petitioning Constantinople for years, rose in support of the imperial fleet.
Martino was defeated, taken, and carried off to Constantinople, where he spent years in prison. Chios returned to Byzantine rule.
It kept it for seventeen years.