Why might have the philosophy of communism appealed to many 19th century factory workers?
This is a great question. It is probably best to start off with a definition of communism. Communism is the idea that all property, means of production, and whatever else belongs to the community but most likely state. Another goal is to create a classless society. A good example of this would be the former Soviet Union and China.
This idea of common ownership and a classless soceity would certainly appeal to a certain segment of the population, namely, those that work hard and have little to show. In other words, something like this would appeal to the hard working factory worker of the 19th century who does not have hopes for a better life. This can be better appreciated when we consider the harsh working conditions of factory life back then. Equality would be something that they would want.
Those who would not like this ideology would be the wealthy who stand to lose much.