Venetian Charter of Ivan Alexander

Where every other charter here grants land and immunity to a monastery, this one regulates a foreign trade. It is the settlement of a running quarrel: unlike Byzantium, which let Venetian merchants trade duty-free, Ivan Alexander's chancery held them to a firm fiscal policy, and had confiscated the goods of Venetian nobles who refused to pay. The charter fixes the terms that ended the dispute — a 3% duty, scheduled port and weighing fees, judicial protection against seizure, and the right to build churches and loggias — and so opens a rare window onto the customs regime, the coinage, and the Black Sea ports of the fourteenth-century empire.

It is also a document of the tsar's own person: he swears the privilege on God, the Virgin, the True Cross, St Petka of Tarnovo and his own soul, and closes by branding any who break it a traitor to his empire.

The privilege followed years of friction over customs on the Black Sea coast — the Venetian senate was moved to treat with Bulgaria after nobles such as Niccolò Pisani and Lorenzo Foscarini lost goods worth 1,000 and 4,000 hyperpyra to seizures ordered by the tsar. Its oath on St Petka of Tarnovo is pointed: her relics, brought to Tarnovo by Ivan Asen II after Klokotnitsa, made her the city's protector. Because Bulgaria struck no gold, the hyperpyra it reckons in are Byzantine coins then circulating on Bulgarian markets. The named ports — Sozopol, Anchialo, Mesembria, Varna, Kilia and others — map the empire's Black Sea trade.