Wednesday, June 28, 2023

About Middle Ages Naval Logistics

I am reading a book titled Medieval Maritime Warfare, by Charles D. Stanton. I mention it here because it has some interesting stats on what it took for an amphibious invasion in the 11th century. Unless you are an experienced wargamer or a historian, most of us have little idea of what it takes to move a medieval army across a body of water, even one as narrow as the Channel between France and England. The book covers a wide spectrum of “medieval naval warfare,” starting with the Crusades and the rivalries between naval powers in the Mediterranean. It continues with William the Conqueror’s invasion of England. It is particularly eye-opening.

An educated estimation establishes William’s troops at 8,000 on the field at the Battle of Hastings. In addition to this, another 2,000 were left to garrison Pevensey and Hastings about 10-15 miles south of the battle site. Another 4,000 mariners were needed to man the fleet across the Channel for this many troops, or about 700 vessels of various types. That’s about 5-6 crew per vessel—most of those were longship-like, alongside fewer larger ships like cogs fitted for war and with larger crews. This also means that infantry aboard the longships would have manned the oars if they had been needed, Norse-style as one should expect of Normans. The fleet actually used sails to navigate up the French coast and across the Channel. According to the quoted historian, the invasion force would have required “approximately” 28 tons of unmilled wheat grain and 14,000 gallons of water, or that is to say a daily ration of 4 pounds of grain and 1 gallon of water per man.

About 2,000-3,000 of the 10,000-strong invasion force were knights with at least as many warhorses, plus palfreys for the knights and their squires, and pack horses. The most valuable mounts were 15-16 hands tall and weighed about 1,500 Lbs. each. They would have needed about 14-20 tons of grain per day, or 13 Lbs. of grain per warhorse per day. The author does not provide figures for the other horses. One might assume at least two palfreys and one pack horse per knight at the minimum. Assuming these horses ate half as much as warhorses, that’s still an extra 21-30 tons of grain for those mounts, for a grand total of 63-70 tons of grain for the entire invasion force… per day. Water for the horses wasn’t mentioned. Figure 6-10 gallons of water per horse per day. This would have amounted to another 80,000 gallons of water approximately.

Unsavory details concern the sanitation involved in keeping the invasion still for a month before launching it across the Channel. The author goes on to quote that the horses would have produced 2,500 tons of feces and 700,000 gallons of urine per day. I question this latest figure, however. If the invasion force consumed some 94,000 gallons of water per day, how does it produce nearly ten times as much urine? Typo? Regardless, the duke would have needed an extensive body of workers to remove the waste and keep the invasion force properly supplied, all this at his own expense. Many of the troops, ships, and their crews were feudal forces only available for a few months each year, after which their service would no longer be due to their duke. They weren’t actually paid like professional troops of later centuries. At any rate, William had a limited window during which he could conduct his invasion.

How does this relate to RPGs? It doesn’t unless you want to run dominions and plot events like wars between realms with a modicum of realism. RPGs allow for magic users and clerics who would have a direct influence on medieval-like logistics, healing, sanitation, transport, communication, intelligence, and tactical support in general. Those are really up to the game masters. Imagine what the figures should be for an army fielding ogres, trolls, or giants. Mind you, I did figure out the logistics of using dragons. Click here for this and look under Feeding and Logistics. Have fun storming the castle!