Black people and women in the US got the right to vote just in the past century. What about that says STEM to you?
One of the big differences at the time was the use of "repeaters" by the North. Having a gun that can shoot again quickly when the other side cannot is a huge advantage.
With the North winning the Civil War, they put both Reconstruction and the 15th Amendment in place, causing Blacks to have the right to vote (of course many people tried to thwart that law for almost a century).
[0] - https://www.history.com/topics/american-civil-war/civil-war-...
Same applies to coordinated protest activities.