What combination of events was responsible for the Civil Rights movement gaining more national support in the mid-twentieth century, as opposed to the 1910s and 1920s?

Help me study for my History class. I’m stuck and don’t understand.

What combination of events was responsible for the Civil Rights movement gaining more national support in the mid-twentieth century, as opposed to the 1910s and 1920s? How did civil-rights activists from the 1950s-1960s compare with earlier activists regarding strategies and objectives? Include specifics from Week 15 lecture and relevant details from Chapters 19-20, 22-24.

Part I: Sets the stage with postwar developments like GI Bill, Interstate Highway Act, suburbia, white flight:

https://www.youtube.com/watch?v=6-W5c60lskA

Part II: Brown vs. Board, Emmitt Till, Rosa Parks, Montgomery Bus Boycott, Martin Luther King, Sit-ins

https://www.youtube.com/watch?v=cflxROenk_w

Part III: Ella Baker, SNCC, Freedom Rides, Birmingham Children’s March, King’s Letter from Birmingham Jail, Civil Rights Act of 1964, Voting Rights Act, 1965

https://www.youtube.com/watch?v=FVGFPHLF5RM

Part IV: Rise of black nationalism (Malcolm X, Stokely Carmichael, Black Panthers), urban riots, Johnson’s Great Society

https://www.youtube.com/watch?v=W-oB_C9w39w