TheKapudan Pasha (Ottoman Turkish:قپودان پاشا,modern Turkish:Kaptan Paşa), also known as theKapudan-ı Derya (Ottoman Turkish:قپودان دریا, modern:Kaptan-ı Derya, "Captain of the Sea") was thegrand admiral of theOttoman Navy. Typically, the Kapudan Pasha was based atGalata andGallipoli during the winter and charged with annual sailings during the summer months.[1] The title ofKapudan Pasha itself is only attested from 1567 onwards; earlier designations for the supreme commander of the fleet includeDerya Bey ("bey of the sea") andRe'is Kapudan ("head captain").[2]
The titleDerya Bey as an official rank within the Ottoman state structure originated during the reign ofBayezid I (r. 1389–1402). Following the 1453conquest of Constantinople,Mehmed II raised Baltaoğlu Süleyman Bey to the status ofsanjak bey for his efforts against theByzantines in theGolden Horn.[1] Baltaoğlu received thesanjak of Gallipoli (the principal Turkish naval base) and thekazas of Galata (until the Conquest aGenovese colony) and ofİzmit (whose tax remittance consisted of ship timber).[1]
The success ofHayreddin Barbarossa (c. 1478-1546) saw the Kapudan Pasha elevated to the ranks ofbeylerbey andvizier in 1535, with his territories expanded into theEyalet of the Archipelago andAlgiers. Hayreddin's successors succeeded to these holdings, but saw their rank drop totwo-horsetail vizier for several centuries.[1]

The official residence of the Kapudan Pasha was in theDivankhane in theImperial Arsenal in the Golden Horn, but the Pasha was often away as governorship of the Eyalet of the Archipelago entailed visiting its various provinces in person every year.[2] The post was one of great power and prestige within the Ottoman hierarchy:Evliya Çelebi reports that it had an annual income of 885,000 silverakçe. Additional income, to the amount of 300,000kuruş in the 18th/19th centuries, came from leasing a number ofAegean islands totax farmers (iltizam).[2]
The heyday of the post of Kapudan Pasha came in the 16th century, when a succession of capable holders brought Ottoman naval power to its height, and for a time ensured its supremacy in the Mediterranean.[2] Although in theory the post could only be filled by a servingadmiral (Kapudan-i Hümayun), a chief of the Imperial Arsenal (Tersane Kethüdasi) or, at the very least, by thesanjak-bey ofRhodes, from the turn of the 17th century the appointment of courtfavourites and/or persons lacking in military or naval experience marked the beginning of Ottoman naval decline.[2]
Beyond naval command, the Kapudan Pasha held direct gubernatorial authority (asBeylerbey) over most of the Aegean islands (theCezayir-i Bahr-i Sefid Eyalet), making him responsible for their administration, tax collection, and shipbuilding resources, effectively merging high naval command with significant provincial governance.[4]

As a part of theTanzimat reforms of 1839-1876, the Eyalet of the Archipelago was reduced in rank and granted to thewali of Rhodes in 1848. The Kapudan Pashas retained their rank, but were thereafter solely military servicemen.
A total of161 captains served until 13 March 1867 when the post of Derya Kaptan was abolished[5] and replaced by ministers (Bahriye Nazırı) of theOttoman Naval Ministry. After 1877, these were replaced by theFleet Commanders.