By the 1690s the long contest between the Republic of Venice and the Ottoman Empire had ground on for years as part of the Morean War. Late in 1694, Venice had seized Chios, the prosperous Aegean island famous for its mastic and its strategic position off the Anatolian coast. Holding it was another matter. An island so close to the Ottoman mainland could only be kept if Venice controlled the sea around it, and the Ottomans, with their Algerian allies, were determined to take it back. The two fleets that gathered near the Oinousses in February 1695 were fighting not over the islets themselves but over the lifeline of supply and reinforcement that any Venetian garrison on Chios would depend upon.

The first engagement, on 9 February, was a clear Venetian defeat. Three ships were lost outright, blown up in the fighting, among them the Stella Maris, the Leon Coronato, and the Drago Volante, their names preserved in the battle's grim ledger. On the sailing ships, 142 men were killed and 300 wounded; on the galleys, the toll was heavier still, 323 dead and 303 wounded. The second clash, ten days later on 19 February, found the Venetians weaker, short the three lost ships and the damaged San Vittorio, and facing a fleet that outnumbered them. That action ended in a draw, with 132 more Venetian dead and the warship Fama Volante damaged. Two Ottoman vessels were hurt as well. A draw, though, was not enough to save the campaign.

It is easy to read a battle like this as a list of ships and numbers, but the figures stand for men. In the first engagement alone, well over four hundred sailors died and more than six hundred were wounded, crowded onto wooden decks as cannon fire tore through rigging and hull. These were the rowers and gunners and ordinary seamen of two empires and a North African regency, fighting in winter seas far from home, many of them pressed into service or fighting for pay. When a ship like the Drago Volante blew up, it took most of a crew with it in an instant. The barren islets that gave the battle its name watched hundreds of these lives end over ten February days.

Tactics and casualties told only part of the story; the strategic verdict was decisive. With his fleet battered and his command of the surrounding waters broken, Zeno could no longer guarantee the supply and defense of Chios. The Venetian position on the island became untenable, and the garrison was forced to abandon the prize it had won only a few months earlier. Mezzo Morto Hüseyin, the Algerian admiral who had pressed the attack, had achieved his aim without needing a crushing victory; he had simply made Venice's grip impossible to hold. The Oinousses islands returned to obscurity, their few rocks once again of interest to no one but fishermen, and Chios passed back into Ottoman hands.