What effort was aimed at breaking the will of Southerners

I think the answer is the battle of Gettysburg

Explanation:

"the sepoy rebellion was the result of many, many influences and stressors on the cultures of india living under british rule. in britain, it's called the sepoy mutiny on the indian mutiny, but in india, it's called the first war of independence.

the main reason is concerned to the british paramountcy , the belief in british   dominance in india political, economic and cultural life had been introduced in india about 1820."

"they were forced to grow crops that benefited the colonizing nations instead of feeding their own people."