What was the prevalence of what we in contemporary western culture would consider "ethnic minorities" (Africans, East Asians, South Asians, Latinos, etc) in the population of early 15th century Bohemia? I have heard various conflicting reports on this topic; general consensus seems to be that there were none of what we today would consider minorities in that region during that period, but some people who disagree are citing this article as proof of the contrary. I am not sure whether this source is credible and would like some clarification on the actual facts.
I will try to answer this question. The first mention from Arab merchant Ibráhím ibn Jákúb who notes: Prague is made of stone and lime and one of the biggest cities to trade (965-966,https://cs.wikipedia.org/wiki/Ibr%C3%A1h%C3%ADm_ibn_J%C3%A1k%C3%BAb). In 1348 the king Charles the fourth was elected as Bohemian king after his father Johann von Luxemburg. He tried to make Prague, our capital city, a center of trade. He founded the university which is now called after him (https://en.wikipedia.org/wiki/Charles_IV,_Holy_Roman_Emperor).
In those days in Bohemia were some of those minorities – Jews, Gypsies. After Charles the fourth died (1378) his son Wenceslaw the fourth took his place (approximately around 1403). He was as good as his father.
The center of trade declines. Then the reformation of religion started. Our reformator Jan Hus preached about catholic priest bureaucracy (https://en.wikipedia.org/wiki/Hussites, that all for political situation).
To make it clear there are not such evidance that there was an actually minority of black people in medieval history of my country (https://blisty.cz/art/73195-nikdy-se-nikdo-takovy-v-ceskych-dejinach-nevyskytoval.html). The symbols usually of black collered people represent something bad ( black woman- ugly, stinky; a groupe of black guys with steel sticks- falus symbol at so on). A discovery of man with negroid sight was foun in Prague historian Petr Charvát claims that the man was part of mission of Saints Cyril and Methodius. Another typical thing was a black kid as toy ( bought at Mediterraneans harbour) for aristocratic children. On of the moust famous black man what lives in Prague was Angelo Solimar (1721-1796;https://en.wikipedia.org/wiki/Angelo_Soliman). He was a servent of Lichtensteins, suppost to be friend with Mozart. For other discovery of black people in Bohemian history was occasional ( for example on coronation ceremony of Maxmillien the second) and it was only an attraction for people. This days (2018) Bohemia is content with wave of racism leaded by czech-japanise Tomio Okamura and his political party SPD.