>>96794770
>diverse and vibrant immigrant community present in the empire
Unironically this has always been the case but only in some places and under very specific circumstances, and they did not assimilate into the Empire and were segregated into designated ghettos (for American retards: a ghetto is not necessarily the impoverished black shithole you're imagining) within major trade hubs like Marienburg.
TLDR fuck no there were not black African Empire soldiers, but maybe one or two from wealthy immigrant merchant families became Othello or Alexander Pushkin-esque respected burghers or maybe even minor nobles in very isolated and exceptional incidents.