Keeping food over long periods of time was a great challenge in the pre-industrial world, before refrigeration. Even things like ice boxes ( and icemen to fill them) didn't become a common thing until the later 19th c. , after ice was developed as a commodity. The methods were few: but most still exist. Some things could be salted- fish, pork and beef. Some things could be kept in brine and allowed to ferment- ( pickled cucumbers, sauerkraut, kim chee) Some things could be dried- fruits, beans, fish, and other meats. Some meats could be smoked. Sugar could be used, as well. And if there was a place that was relatively cool and dry, salted meats could be hung and kept for a very long time. Potassium nitrate, sodium nitrate, wood ashes and even lye could be employed ( Norwegian lutefisk)

Hams and sides of bacon were generally salted, smoked, and hung in a dry larder. Sometimes they were also painted with a sugar solution as well. The salt content was high enough, however, that to be consumed they would typically be first soaked in water. To quote Lydia Maria Child's The Frugal Housewife:

The old-fashioned way for curing hams is to rub them with salt very thoroughly, and let them lay twenty-four hours. To each ham allow two ounces of salt-petre, one quart of common salt and one quart of molasses. First baste them with molasses; next rub in the salt-petre; and, last of all, the common salt. They must be carefully turned and rubbed every day for six weeks; then hang them in a chimney, or smoke-house, four weeks.

They should be well covered up in paper bags, and put in a chest, or barrel, with layers of ashes, or charcoal, between. When you take out a ham to cut for use, be sure and put it away in a dark place, well covered up; especially in summer.

Some very experienced epicures and cooks, think the old-fashioned way of preparing bacon is troublesome and useless. They say that legs of pork placed upright in pickle, for four or five weeks, are just as nice as those rubbed with so much care. The pickle for pork and hung beef, should be stronger than for legs of mutton. Eight pounds of salt, ten ounces of salt-petre and five pints of molasses is enough for one hundred weight of meat; water enough to cover the meat well—probably, four or five gallons. Any one can prepare bacon, or dried beef, very easily, in a common oven, according to the above directions.

The bacon you find in the grocery now is nowhere near as salty as this. If you encounter country ham ( especially in the southern US) you will get a better idea of what bacon would be. Bacon today also is typically sold sliced up. The bacon in the days of Child ( 1830's) would remain in a large hunk until pieces were sliced from it, and that hunk would be salted and glazed- and likely some more salt rubbed onto where a piece had been cut. Sometimes mold would form over the outside of dried meats- that would be scraped off.

TL:DR your bacon is not their bacon.

​

Before refrigeration the average western diet consisted of 18-22 grams of salt per day because of salt's use as a preservative. In fact American prisoners in the war of 1812 complained bitterly that the 9 grams of salt per day that they were being rationed was meager.