There remain ~40M slaves in the world.

Slavery was everywhere in the world, for centuries, until a successful movement to end it started in England and spread worldwide. But slavery is still not fully eradicated, including in pockets of Africa that still have chattel slavery. There remain ~40M slaves in the world. https://t.co/YZ1gRFVdeT

— Nicholas A. Christakis (@NAChristakis) July 16, 2022