No maths (the earliest records of maths beyond simple counting come from Africa, on the Ishango bone, and historians think Greek and Roman mathematicians learnt from African scholars), no electricity (Alternating current which carries most of your electricity was developed by a Serbian immigrant: Nikola Tesla), as well as no rap music (so no ERB), blues, hip hop (no Hamilton), reggae, soul, jazz, gospel and grime. Those are all MOBOs. No moon landing. No John Glenn flight. Longer WW1 and WW2 (Black soldiers did a LOT of the fighting compared to how many there were). In fact, no Neil DeGrasse Tyson. No computer and even longer WW2 (Alan Turing was gay, and gays are a minority), no ironing board. No heart transplants. No Kevlar (Invented by Polish Immigrant Stephanie Kwolek). Yeah.