What Real Medieval Warships Can Tell Us About Game of Thrones

Contains spoilers for the season six finale of Game of Thrones

The sixth season of Game of Thrones ended with a shot that viewers have been waiting on for years: countless warships under the command of Daenerys Targaryen, sailing for Westeros. Fans will have to wait months to find out how her mission plays out, but—knowing that the show draws frequently on real history—perhaps a clue can be found in the real history of how warships worked during the medieval period.

And, if history turns out to be any indication, fans are unlikely to see an epic naval battle start off the next season.

There were two oft-cited types of ship at sea in the Mediterranean during that period, and both were often merchant ships outfitted for warfare. While historians have debated the exact size of these fleets, they are generally thought to have numbered in the hundreds of vessels, according Helen J. Nicholson’s Medieval Warfare: Theory and Practice of War in Europe, 300-1500—which is about right for Game of Thrones.

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The fact that Daenerys’ armies are used to fighting on land may not be much of a drawback for her, even if Lannister ships are waiting: Naval warfare in the medieval period was such that it was usually more about hand-to-hand combat, which took place as the ships drew together, than it was about sinking the enemy’s ships. A multi-tiered defensive structure built into some ships allowed archers to fire down at the enemy’s decks, and soldiers in crow’s nests could throw down down “stones, javelins, darts, and pots of quicklime (a caustic powder),” writes Mike Loades in The Longbow.

Full-on battles at sea were a last resort. “Most often [the goal for the enemy’s ships] was to capture them as prizes, if at all possible,” notes Charles D. Stanton in Medieval Maritime Warfare. Those prizes were how the crewmembers were often paid.

Medieval states generally lacked the bureaucratic underpinnings to support a standing navy, as Susan Rose’s Medieval Naval Warfare 1000-1500 argues. So many medieval naval actions were “logistical support for land operations or the blockade of a hostile port,” Stanton argues. “This is particularly true when one takes into account that the primitive state of nautical navigation at the time, the vulnerability of galleys to inclement weather, and the need for constant resupply constrained medieval fleets to the coastlines anyway.”

Medieval ships were extremely slow and navigation tools provided limited help. Ships also tended to stay close to the shoreline for refuge in bad weather and clean water supplies. As Nicholson writes, “No nation could be said to have achieved ‘control of the sea’ during the Middle Ages, as it was never possible to keep track of where a ship-borne enemy might be in order to attack and eliminate it.” And that’s why Stanton writes that “whoever controlled the shorelines also controlled the seas.”

In other words, the hardest part of what the Queen of Dragons has undertaken wouldn’t necessary have been winning the battle—it would have been getting to Westeros at all.