The war had started in 1768, and Catherine the Great's strategy was audacious: sail Russian squadrons all the way from the Baltic, around Europe, into the Mediterranean, to threaten the Ottomans from a sea they thought was theirs. Two squadrons under Admiral Grigory Spiridov and the British-born Rear Admiral John Elphinstone joined under Count Alexei Orlov and went hunting. On 5 July 1770 they found their quarry anchored north of Çeşme Bay: roughly fourteen ships of the line, frigates, galleys, and small craft, some 1,300 guns in all, commanded by Kapudan Pasha Mandalzade Hüsameddin. The first day's clash was brutal and confused. Spiridov's flagship Sviatoi Evstafii grappled with the Ottoman Real Mustafa; when the burning Ottoman ship's mast crashed onto the Russian deck, both vessels blew apart. Of the Russians, 636 men died on Sviatoi Evstafii alone.

The Ottomans retreated into the bay itself, anchoring in tight defensive lines. It was meant to be protection. It became a trap. Through the day of 6 July the Russians bombarded the crowded ships. Then, after midnight, they pressed in close. Gunfire from the ships Grom and Ne Tron Menya set an Ottoman vessel's topsail alight, and the fire leapt from rigging to rigging across the packed fleet. Into this Samuel Greig sent fireships — vessels deliberately set ablaze and steered into the enemy. One reached its target and the flames spread further still. There was nowhere for the Ottoman sailors to go. The ships were wedged together; the bay was narrow; the night was lit orange from shore to shore. By morning almost the entire Ottoman fleet was ash on the water.

The numbers are stark and they belong to real people. Russian losses were counted in the hundreds. Ottoman losses ran to roughly ten thousand sailors dead — ordinary men, conscripts and crew, most of whom never had a chance to fight back. They were not statistics to the families who waited for them in ports across the empire. Only one large Ottoman ship of the line, Semend-i Bahri, and a handful of galleys survived to be captured. The commanders — Hüsameddin, Hasan Pasha, Cafer Bey — lived; the men who served them mostly did not. It is worth pausing over that gap. The painters who later celebrated the night, the columns Catherine raised in St. Petersburg, none of them recorded the names of the dead.

Chesma was the greatest naval disaster the Ottomans had known since Lepanto in 1571, and its consequences spread far beyond the bay. Russia controlled the Aegean for the next five years and returned to bombard Çeşme twice more. The defeat emboldened Orthodox Christian populations across the Balkans toward rebellion. But the violence also rebounded cruelly on innocents: in the aftermath, mobs in nearby Smyrna massacred around 1,500 local Greeks. Catherine the Great built monuments to her triumph — a palace, a church, an obelisk, a column at Tsarskoe Selo. Today Russia still marks Chesma as a Day of Military Honour. The narrow strait off Chios, so often a place of beauty, keeps the memory of one of the deadliest nights in the history of naval war.