It was used because other people thought Slavic people were the ideal slaves and Europeans enslaved the Slavs.
So because everyone thought Slavs were the best slaves, they just morphed to slave.
It is highly offensive to me that people use the word "slave" because this means that they are automatically saying that I am naturally fit to be a slave and not a human being.
"The oldest written history of the Slavs can be shortly summarised -- myriads of slave hunts and the enthralment of entire peoples. The Slav was the most prized of human goods. With increased strength outside his marshy land of origin, hardened to the utmost against all privation, industrious, content with little, good-humoured, and cheerful, he filled the slave markets of Europe, Asia, and Africa. It must be remembered that for every Slavonic slave who reached his destination, at least ten succumbed to inhuman treatment during transport and to the heat of the climate."
https://www.etymonline.com/word/slave
Because of this, Slavs are still seen as inferior throughout the Middle Ages, and even now, as seen by dumb Polack jokes. By the 1800s, Slavs were subjected to expulsions and massacres by Germanic groups. This anti-Slavic sentiment followed the predictable trajectory of Germanic racism and, a century later, reached its natural conclusion: almost 11 million Slavs were murdered in Hitler’s long list of murdered “subhumans.”
Why were Slavs targeted by the Nazis? They were seen as intellectually inferior and invaders who were living on stolen Germanic land. The German's plan was to eliminate 30 million (!!) Slavs, create room for the expanding Aryan race in the Eastern territories, and enslave the remaining Slavic population
So.....is everyone here, and especially the wokish people, going to immediately and forever stop using the world "slave?" So, that's right...you cannot describe black people brought to the USA as "slaves." Never use the world "slave" as it is known by me as the s-word, and makes me exceptionally angry, just like the n-word for black people. Use another word for the s-word, I don't care what it is, and it's not my job to find one.