The Ottoman Navy (Donanma-yı Humâyûn or Osmanlı Donanması), also known as the Ottoman Fleet, was the naval warfare arm of the Ottoman Empire. It was established after the Ottomans first reached the sea in 1323 by capturing Praenetos (later called Karamürsel after the founder of the Ottoman Navy), the site of the first Ottoman naval shipyard and the nucleus of the future navy.
During its long existence, the Ottoman Navy was involved in many conflicts and signed a number of maritime treaties. It played a decisive role in the conquest of Constantinople and the subsequent expansion into the Mediterranean and Black Seas. At its height in the 16th century, the Navy extended to the Indian Ocean, sending an expedition to Indonesia in 1565, and by the early 17th century operated as far as the Atlantic. Commensurate with the decline and modernization of the empire in the late 18th century, the Ottoman Navy stagnated, albeit remaining among the largest in the world: with nearly 200 warships, including 21 battleships, it ranked third after the British and French navies.
For much of its history, the Navy was led by the Kapudan Pasha (Grand Admiral; literally "Captain Pasha"); this position was abolished in 1867, when it was replaced by the Minister of the Navy (Bahriye Nazırı) and a number of Fleet Commanders (Donanma Komutanları).
After the end of the Ottoman Empire and the declaration of the Republic of Turkey in 1923, the Navy's tradition was continued under the modern Turkish Naval Forces.
The first Turkish naval fleet in Anatolia, which consisted of 33 sail ships and 17 oar ships, was formed at the port of Smyrna (İzmir) by Tzachas in 1081, following his conquest of Smyrna, Vourla (Urla), Kysos (Çeşme), Phocaea (Foça) and Teos (Sığacık) on the Aegean coast of Anatolia in that same year. Tzachas's fleet raided Lesbos in 1089 and Chios in 1090, before defeating a Byzantine fleet near the Oinousses Islands off Chios on 19 May 1090, which marked the first major naval victory of the Anatolian Turks in a naval battle.