Although the details are murky and lost in time, most of the ancient tribes practiced tribalistic polygyny in various forms for thousands of years.
What is fairly possible is that the tribes who practiced polygyny, thus miring themselves in sexual violence, the endless expelling of low status beta young males, rotting of the gene pool, sloth, and the increasing need for rigid control over the young girls.
As monogamy and with it alpha fathering spread across the Western world, it brought with it diligence, self discipline, life long commitment to children, and attention to something besides sex.
The evidence is murky, but the case can be made that as monogamy spread across the world, slavery disappeared in 100 to 400 years.
Indeed, the entire polygamous world was engaged in various forms of slavery, and some of the polygamous world is still engaged in slavery in the 21st Century!
Did monogamy help end slavery?
There are mountains of evidence that support this.