When did showers first appear on warships?
Short answerIt depends on what counts as a shower; bucket-fed arrangements are very old, while a true plumbed installation requires a more precise definition and remains disputed.
NotesSeveral navies claim early shipboard showers while describing different equipment. Some installations had a shower head but required another sailor to pour water through it from a bucket. If any controlled falling water counts, bucket showers reach back at least to the Napoleonic era and probably earlier. A stricter history of plumbing and pumped water would need a narrower definition before naming a first warship or navy.