Blacks were largely a republican/conservative voting bloc after Lincoln freed the slaves and black men were able to vote. The tide began to turn in 1927 after the Great Mississippi Flood. Herbert Hoover promised a lot of shyt to black people during the clean up process, but reneged on his promises after becoming president. That led to many blacks turning to FDR and the New Deal. Still due to the progressive nature of the republican party on civil rights, many blacks did stay with the GOP.
Both Nixon and Kennedy fought over the black vote in 1960, but Kennedy would secure it as president due to his dealings with MLK and the fight for the civil rights act. Johnson secured the black vote by passing the 1964 CRA, and the republican party ultimately burned any good will they had with blacks throughout the late 60s - from Governor Reagan disarming the Black Panthers in California to Nixon's Southern Strategy
The Living Room Candidate - Commercials - 1972 - McGovern Welfare
sound familiar?
So I'll reject the notion that black people are natural conservatives, or that we should be republicans because Booker T Washington (who casually told anti-black jokes to entertain whites in Washington) was a republican. That republican party was more liberal/progressive on civil rights than today's GOP.
Minorities in the US have always been practical voters: they vote for whoever has their best interest in mind. Irish Americans have historically voted democrat due to the anti-Irish resentment of eastern republicans during the 19th century, and the fact that democrats gave them an opportunity to run their own communities politically. Hispanics have voted democrat for decades due to right wing fear mongering on immigration; Bill Clinton won a higher percentage of Hispanics in 1992 than Obama did in 2012, Hispanics didn't vote for Reagan, etc. Cubans have largely been a republican voting block due to the Bay of Pigs, although Obama surprisingly won that group last year. And as I have detailed, blacks voted republican after Lincoln freed the slaves, then voted democrat after the CRA.
In short, when you act like a dikk to entire groups of people, that group won't support you. I respect my black republican friends irl and here, but don't act like the last meaningful thing to happen to the black political experience in the US was a republican freeing the slaves. Stop pretending like dixiecrats didn't largely leave the democratic party in the 60s-70s due to civil rights.