I'm reading "The Ottoman Age of Exploration" by Casale and I've noted that the Ottomans predominantly constructed oared galleys for their Indian Ocean fleet in the 16th century. What was it about Indian Ocean conditions that lead them to favor this kind of vessel? They were up against Portuguese sailing vessels, and had the ability to hire European boatrights, so it was within their power to emulate the Portuguese. Thanks
/u/adenoidcystic
We may never know for sure whether the Ottomans consciously decided to use oared galleys in the Indian ocean in the 16th century, but it is widely accepted that the Ottomans did not use carracks or caravels as the main force of their navy anywhere until much later; all this despite their vassals in the western Mediterranean slowly moving toward fully rigged ships. Thus, it is widely accepted that this may be the case of fighting using the navy that you have, instead of the navy you wish you could have. After all, sailing using fully rigged ships require knowledge in shipbuilding, the ability to supply the relevant materials, and importantly sailors who had the skill to sail them.
It was already well known the pros and cons of a galley in comparison to a fully rigged ship. An oared galley can move entirely through human power, independent of wind conditions. In the Indian ocean, this means that the oared galley can move independently of wind conditions, which were highly seasonal. However, each galley requires a large number of humans, who then have to be fed, allowed to rest, and replenished in numbers. In turn, this requires supply bases in its area of operation, something that that Ottomans had some access to.
As a means of comparison, consider two naval battles around the North Sea:
The Spanish Armada of 1588, fought around the North Atlantic and the North Sea, had 4 galleys and 4 galleasses among its 28 purpose-built warships, requisitioned from their usual theater of operation in the Mediterranean near Naples. The 4 galleys had to turn back due to poor weather in the Bay of Biscay, but all 4 galleasses made it to the theater of battle.
The Genoese fleet of 1603 under Spanish pay included 8 galleys, commanded by Federico Spinola (brother of Ambrosio Spinola). They fought in the Battle of Sluis where despite sinking one Dutch ship and killing almost twice as many Dutch sailors than they lost, they had to retreat after Federico was killed in action.
So even in theaters that do not necessarily favor their means of conveyance, galleys can and were used up until the 1600s.
See: Maritime Transformation in Comparative Historical Perspective by Erckson, Goldstein, et al.; The twilight of a military tradition: Italian aristocrats and European conflicts, 1560-1800 by Mark Hanlon.