Hussar
Legend
Why are you insisting on "realistic" naval combat? You appear to be the only one who needs this in order to differentiate from pirate genre movies.Me, probably REH, and the other people who made modern pop culture. Pirates of the Caribbean was based on a 1967 Disneyland ride which was based on a 1950 movie version of the 1883 novel Treasure Island. But as I said, apart from having more fantasy it isn't much different. No realistic naval combat. The only recent movie to attempt that was the not-a-pirate-movie Master and Commander. And Greyhound I suppose. The Battle of the River Plate (1956) is a pretty authentic naval engagement movie. It's set in 1939, but a lot of the age of sail parameters were still in place. It was the battle of Midway in 1942 that changed all that.
I do seem to recall a rather large number of pirate movies where you have crews fighting other crews on ships. Doesn't need to be realistic. And, as I've been saying all the way along, as soon as you have about 50 combatants, D&D fails hard.
And, as far as Conan goes, there are a LOT more Conan authors than just REH. Like, literally dozens, and hundreds of novels.