>>717823243
>Slave trade was a pagan thing. It ended in Poland and Czechia almost immediately after christianization.
Not at all. The Christian kingdoms were literally built on being major slave rings with Christianity of the seller being the requirement for Frankish, Venetian and Byzantine buyers.

Read some papers like "Slavery in Árpád-era Hungary in a Comparative Context". It focuses on the Kingdom of Hungary and its slavery which only started fizzling out around the time of the Mongolian raids but it also touches on the topic of Poland and Bohemia functioning similarly in this regard. Not surprisingly as the three kingdoms did share a very similar position and developments (with Bohemian crown lacking the direct Orthodox neighbor and being directly part of HRE giving it some minor oddities compared to the other 2).