After spending some time on a Caribbean island and getting burnt I'm curious how sailors or other Europeans living or sailing in the area during colonization dealt with sunburn.
Hi there, I answered a similar question awhile back in what turned into quite a lively thread; it's archived here.
To quote from that answer:
Ideally, sailors would deal with sunburn by not getting it. Traditional dress for sailors would include loose pants, long-sleeved shirts and broad-brimmed hats, and sailors would stay out of the sun under awnings and other shade if possible. When they inevitably did get sunburned, they could use a salve of some kind of grease (often "slush" from cooking kettles) to help with the pain/blistering. Many no doubt just burned until they became deeply tanned, in the manner of sailors today. Also, the thread u/kentonj linked elsewhere deals with long-term effects (on mobile, can't link to it directly).