You can push that all the way back to the Middle Ages. Serfdom was quite an improvement over Roman-era slavery, being tied to the land was far more stable and s

You can push that all the way back to the Middle Ages. Serfdom was quite an improvement over Roman-era slavery, being tied to the land was far more stable and secure than being tied directly to a master. It wasn't quite a middle class, but better nonetheless. Transportation and naval technology steadily improved, and more and more goods and services became broadly available during this time period. The downside is that war got really bad from 1800-1950.