i also finally got to grips....well in a hazy way...with the 1900s-today history of harlem yesterday morning. which is basically:
iproperty developers build a load of lush fancy houses for rich people to move into, in a good location, in manhattan, easy to get to midtown, an extention of the upper west and upper east sides. it totally failed as property speculation due to the great depression, economic downturn. black people couldn't live hardly anywhere in nyc coz of discrimination redlining etc, and were dispersed around the city rather than there being specific black neighborhoods are there were later, and they all moved up into this suddenly available cheap and nice housing. then a flowering of black culture in harlem, ie the harlem renaissance, somewhat marcus garvey inspired. then nonetheless everyone is still fucked by redlining, only being able to get low wage jobs, discrimination in education etc, gradually turns into all these people crammed into houses with lodgers etc that were built for single families, a lot of poverty. then heroin arrives in the 50s and fucks everything further, the city goes through the 70s bankrupt phase, the dangerous and lawless nyc that everyone knows about emerges, shit gets hairy, crack arrives in the 80s and further further fucks everything, landlords start burning down their buildings for insurance or otherwise let them decay
then usual nyc story of how everything gets more organized and law abiding in the 90s and 00, then the usual gentrification story, with an added component of african immigration
within all of this as well there's the emergence of jazz, hiphop and graffiti, not just from harlem but it seems to have been a big player in all of these forms, and they're three pretty central and influential forms in culture nowadays obviously. oh and a$ap rocky