The reason there was slavery in the United States is because there was more work to do than people to do it. The North's population grew quicker than the South's, so they could become "moral"quicker
Maxine is an great place for travel I’m in speaks
what caused it was the Japanese army invaded a lot of places so the Japanese govt. became more powerful.
Mass production of goods resulted in the use of mechanization to have an oversupply. Some labor work were replaced by machines, which created unemployment and change of needed skills for an upgrade. Common work can be done by machines while the craft was still handed down to skilled workers. There was a high demand for buying machines that can reproduce products faster.
Because they yearned for freedom.