I'm sitting here peeling this orange in Ohio that has got to me via WALMART and it's vast, fast, and frankly terrifying network. That network drags these fruits from several states away, if not nations away, and delivers it to my table with barely an effort from me except a little money. A lot goes into that orange. Even people from my own State, but living before cars and refrigeration, and especially during the age of sail, they couldn't just get an orange. Maybe if they were king. Normal people couldn't just ward off scurvy with a few oranges from Florida. The oranges wouldn't survive a journey by wagon from there certainly.
So other than citrus fruits, what have people eaten throughout history to take the place of citrus?
Pre-industrial people's of the northern hemisphere had numerous sources of sufficient vitamin C. Fish was a common part of the diet, either fresh or dried and salted. Pickled vegetables including cabbages, cucumbers, and tomatos are also sources of vitamin C. Early explorers and settlers to North America would sometimes brew a tea out of the needles arbor vitae tree, or some other types of evergreen trees.
In additon to cabbage, most of the other Brassica vegetables (including cauliflower, broccoli, brussel sprouts, etc) have fairly generous amounts of vitamin C, and would have been a essential part of the diet of high-latitude agricultural peoples.
hi! you may be interested in a few earlier posts
About vitamin C, scurvy, and the likelihood of developing it
How did people get vitamins 5000 years ago? - featuring /u/restricteddata
How did native peoples avoid deficiency-based diseases like scurvy and rickets?
What treatments did countries try to use before they learned to prevent Scurvy?
Misc sources of vitamin C