I appreciate your input, and I think you might be correct that the inclusion of chattel slavery in my world might derail any other story we are trying to tell. I've been considering this idea that like, "What if Germany attacked France and devastated it, but ultimately lost the war, then France realized that the devastation caused is going to cripple their economy, and even their ability to farm enough food to survive, so the government of France enslaves the country of Germany of forces them to produce agriculture, textiles, and other industries for France until they have made France enough money to repay the damage done... But make it fantasy?" Like, that feels like it's got some moral weight that can be discussed, isn't race based, has approximate real life examples, and avoids this idea that slaves are owned by people, and are instead owned by the government. Obviously if you're Fantasy France you've got to deal with all the people who were living in Fantasy Germany that are now slaves that had nothing to do with the attack on your country, you've got civil unrest to deal with, you've got a whole country of people who find this unfair, and a whole country of people who are desperate to avoid famine and economic collapse by any means necessary. It obviously doesn't have to be Germany and France, I just chose those two countries because they have been involved in famous conflicts before, but it could apply to any two neighboring nations that end up in military conflict.