History of the pig, from when it was first domesticated, through their treatment by various different cultures, until the state of the pork industry today. The pig is unique among farm animals in that unlike other animals that are useful for various tasks, pigs are only raised for their meat. They are omnivorous, eat pretty much anything, and get fat in about 6 months.
In many societies, pigs were scavengers that ate garbage in the streets, acorns in the forest, even human excrement, thus they were considered dirty and associated with poor people. Jews refuse to eat them, which is a part of their identity, although originally the ban on eating pork wasn’t unusual since pork wasn’t eaten in that society at all. Pigs fend for themselves under a variety of circumstances without any human supervision; in both city and forest environments they can find food and quickly multiply, so they’re a convenient source of meat.
This was the state of pigs until after WW2, when we started caring more about efficiency, and raised pigs in intensive farms that are more efficient and squeezed out the traditional farms. However, this poses ethical dilemmas, as pigs in intensive farms suffer an extraordinary amount: they live their whole lives in concrete buildings with no light and no space to move around. Ultimately it’s a tradeoff between morals and cost — it’s possible to raise pigs the old-fashioned way, but would render pork several times more expensive, and very few people are willing to pay the price.