What happened to juarez didn’t pay the war debt ?

With no other options, Juárez suspended payments on Mexican debt for two years. In response, representatives from the Spanish, French, and British governments met in London, and on October 31, 1861, signed a tripartite agreement to intervene in Mexico to recover the unpaid debts.

answer; people where able to travel across the u.s.a faster than any other mode of transportation,travel time was about a week,from coast to coast

the second significant cause of the great migration was the desire of black southerners to escape segregation, known euphemistically as jim crow. rural african american southerners believed that segregation - and racism and prejudice against blacks - was significantly less intense in the north.