The ending of the civil war between the North and the South. Between the end of Segregation in 1877 and the starting of civil rights movement in the 1950's.
They issued the bolsheviks into power
Replaced how? If you mean like the Roman empire, that would be incorrect. Both empires considered each other Roman and both empires considered themselves Roman. So when the west fell, the Byzantines did not 'replace' the western Romans in being Roman. Instead, they just kept on being Roman as their western counterparts fell. However, for a period, the Byzantines did manage to reconquer parts of the Western Empire and even Rome, but that was relatively short-lived. In that case, you could argue that the Byzantines sort of did replace the western Romans in being the Roman empire with Rome in its possession. However, that is a stretch in my opinion.
In short: False, the Eastern Romans did not replace the western Romans as they were both seen as Romans, just with different governments.
Absolutly True. Women like Harriet Tubman established a precedent for others even later.