> There are over 1 million Black people in Central Europe today. Most Europeans still don’t know of the long history of the Black Diaspora in their countries. As a result, there is a general assumption that Black people are a relatively new presence on the continent and thus are historical and national outsiders. Through historical investigation, Black Central Europe challenges these assumptions.

That's very sneaky phrasing, implying that the 1 million Black people in Central Europe today come from this thousand year old Black Diaspora of undefined size, instead of being recent arrivals.

Population statistics are oddly absent on blackcentraleurope.com, but according to [1], "there are roughly 12.5 million Black people in Europe" and "More than 1,000,000 sub-Saharan Africans had settled in Europe between 2010 and 2017."

At that immigration rate, it would take only 87 years (one lifetime) for all of those 12.5 million to enter Europe (ignoring death and birth-rate). That immigration rate was probably not constant [2], but it's more than enough to say that the vast majority are "a relatively new presence".

[1] https://en.wikipedia.org/wiki/Black_Europeans_of_African_anc...

[2] Finding Black population history numbers in Europe is surprisingly difficult, possibly because "many European countries refuse to collect racial data on their citizens": https://qz.com/1236213/europes-black-population-has-increase...