Economic reasons.
slavery in the Americas started when the Europeans came over and they started to enslave the native people
Slavery started many thousands of years ago, it was a worldwide occurrence. The underground rail road was an escape route for slaves in the US
They were people who were against slavery for various reasons.
Slave trade abolished 1807, and slavery itself 1833 - in the UK, and all the British colonies worldwide. As for when it started, there had always been feudal serfdom, which is the equivalent, though of course there wasn't a racial dimension.
Normally for economic reasons
George Washington wasn't born yet when slavery started. Slavery started in the American colonies in 1620 and George was born in 1732. Slavery in general has existed for millennia.
Some people were against slavery for moral and ethical reasons, believing it to be a violation of human rights. Others opposed slavery for economic reasons, arguing that it hindered free labor markets. Additionally, there were those who believed in the principles of freedom and equality, seeing slavery as contradictory to these values.
slavery started in 1440 when Portugal started trading slaves to western Europe
Slavery was and remains a worldwide problem. It has been acceptable by governments and individuals alike when it has suited their purpose.
Being as slavery started many thousands of years ago there are no records of an exact date.
you did
1600s