I’m very interested in history but not well-versed. I have found the battle of Jutland to be very interesting but one thing that I couldn’t figure out is why the battleships had over 1000 men on them? Did it really take that many to run things? Or were they doubling as transports? Or is it something else that I’m completely missing?
Battleships and battlecruisers had large crews because they needed that many men to operate them. A large par of this was because the ship required manning around the clock. The majority of the crew were divided into two watches, named port and starboard. These were further subdivided into two quarters, as only a quarter of the men needed to be on duty at any time when the ship was in harbour. The watches were on duty for four hours, then had four hours off. The one exception was the two dog watches, which were two hours long. The dog watches meant that men did not have to stand watch at the same time each day. However, there were exceptions to the watch system. The stokers (engine room crew) were divided into three watches. There were also daymen, which comprised groups such as the stewards, cooks and medical staff. These positions did not have to have someone on duty 24/7, and so were not divided into watches. Each watch was divided into four main groups, the 'parts of the ship'. In a hangover from the warships of the age of sail, these were called the forecastle, foretop, maintop and quarterdeck. Each part was responsible for their particular area of the ship. When not in action, they would keep this area clean and tidy, as well as performing other routine duties. These other duties included look-out duty, manning the helm, maintaining the magazines, or manning the boats in case of man overboard.
In action, a large part of the crew would be operating the armament. Taking the example of the 15in Mk I mounting that was used on the Queen Elizabeth and 'R' class battleships at Jutland, these had a crew of roughly 70 men. Each of the two guns in the mounting had a crew of eight men: a gun layer, two loaders, a rammer, a breech operator, an ordinance artificer (a trained mechanic present in case of a jam), and the Captain of the Gun, who led the gun crew, plus an 'interceptor operator' who was there to disable the gun in the event of an emergency. Two other men were in the main gunhouse - the trainer, who controlled the facing of the turret, and the 2nd Captain of the Turret. Four men were in a control cabinet at the back of the gunhouse; a rangefinder operator, a periscope operator, a communications rating and the Captain of the Turret. Below the gunhouse was the 'working chamber', where the shells and charges were transferred from the hoists that ran to the magazines and shell rooms to the hoists that ran to the turrets. This had a seven-man crew. The magazines, which contained the propellant charges, had a crew of 19, while the shell rooms had a crew of 21. There might also be others present to run emergency generators or to replace casualties amongst the crew. The Queen Elizabeths and 'R's had four turrets each, totalling ~280 men in the main armament alone. The 12in and 13.5in turrets used on older ships would have slightly smaller crews, mainly in the shell rooms and magazines. However, ships mounting these weapons often had more turrets, so a similar number of men would be manning the main armament on each ship. Then we must consider the secondary armament. Most ships mounted either 4in or 6in guns as a secondary armament for use against torpedo boats and destroyers. These had a crew of four, plus up to six loaders, with ships mounting between 14-16 of these weapons. Then there were more men in the magazines and shell rooms used by these weapons. Ships also carried a torpedo armament. Depending on the size of the armament, this might require up to a hundred men to man it (though this is confused by the fact that the RN's torpedo branch was also responsible for low-power electrical engineering aboard ship). Finally, there were 25 men manning the fire control positions. As such, roughly half of the crew would be manning the weaponry in action.
Another significant fraction of the crew would be manning the engines. The typical battleship had about 200 men as its engine-room crew. Not all of these were needed to operate the engines in action. Instead, roughly a third would form damage control parties, along with other seamen who had no useful duties during a battle. Some men, like the ship's carpenters, blacksmiths and shipwrights, would be part of these parties as a matter of course. Still more men were needed on the bridge. This included not just the officers who commanded and navigated the ship, but also lookouts and spotters, signallers and searchlight operators. This might include up to 100 more men. If the ship was the flagship of a squadron or division, this number might climb even higher. Typically 1-200 of the ship's complement were Royal Marines, providing the ship with a landing party in case of need. The Royal Marines usually also provided the ship's police and sentries. However, in action, they would be manning one of the turrets and a portion of the secondary armament, and should not be double-counted.
It was mostly because yes you did need that many people for doing everything that needed to be done, to the margins acceptable for both the heat of battle, and running a massive warship 24/7.
If the ship just needed to fight for a few hours and then nothing else you could get away with a smaller crew. But you also needed it manned and sailing before and after the battle. Those are watches to be manned, work centers and stations to be crewed all day every day. The engines alone might require 100's of men at a time, and while the era of shoveling coal into furnaces was giving way to oil it was not gone entirely. And oil brought a whole new series of machinery that required constant monitoring and maintenance.
Additionally there was still relatively little automation in many processes. Massive shells for the main guns had powered or hydraulic lifts, but still required men to haul them out of the magazines and same for the bags of powder as most designs had separate shell and propellant.
Ships also had a nasty habit of taking damage in battle. Damage Control parties were also needed when preparing to go into battle. While every man could help, having these men set aside to respond as needed could be crucial, and another requirement for bodies, often these men would be drawn from men who were in the off watch but werent needed at their normal work center or task.
Another potential addition would be a Flag Staff. An Admiral in command of a squadron or other fleet element would have a staff with him, officers responsible for various parts of planning, and enlisted men to serve as attendants, communications staff, etc.
/u/thefourthmaninaboat had a wonderful breakdown of Royal Navy battleship crews in WW1, and some of the unique aspects for the Royal Navy vs other nations. Each one had their own quirks but for the combatants in WW1 there was in essence something of a unified tradition in the seagoing services, they were alike in a staggering variety of ways. Part of it cultural in origin, part just because they represented best practices.
It’s such an interesting and short lived period in naval history. Thank you for the additional info!