Question

How did the Ostend Manifesto help start the Civil War?

The South was outraged over the secret manifesto to defeat slavery.
Northerners were outraged over the South's violent invasion of Cuba.
The South had succeeded in gaining more land in Cuba to expand slavery.
Northerners were outraged at the South's secret attempt to expand slavery.

Answer 1

The south had succeeded in gaining more land in Cubs to expand slavery