What caused people to believe so strongly either for or against slavery and how could this divide a society ?

Interest

Explanation:

The people interest in slavery is what sets the difference. People found slavery to be rewarding and venture into the business of slavery without looking at the fact that the humans used in the slavery are also humans like them. On the other hand the people against slavery might not have a good interest in slavery and understood the fact that human beings are meant to be treated as equals ,these set of people fought against it and that is what shaped the world today. This disagreement can divide a society, because a society built with a common interest will always agree together and such can of society will grow. But a society where there are different opinion divides the society and kills the founding interest of the society .so the different in interest is what can divide a society, so the different interest of slavery among the people in the society is what divided the society.

  Black and white abolitionists in the first half of the nineteenth century waged a biracial assault against slavery. Their efforts proved to be extremely effective. Abolitionists focused attention on slavery and made it difficult to ignore. They heightened the rift that had threatened to destroy the unity of the nation even as early as the Constitutional Convention.

Although some Quakers were slaveholders, members of that religious group were among the earliest to protest the African slave trade, the perpetual bondage of its captives, and the practice of separating enslaved family members by sale to different masters.

As the nineteenth century progressed, many abolitionists united to form numerous antislavery societies. These groups sent petitions with thousands of signatures to Congress, held abolition meetings and conferences, boycotted products made with slave labor, printed mountains of literature, and gave innumerable speeches for their cause. Individual abolitionists sometimes advocated violent means for bringing slavery to an end.

Although black and white abolitionists often worked together, by the 1840s they differed in philosophy and method. While many white abolitionists focused only on slavery, black Americans tended to couple anti-slavery activities with demands for racial equality and justice.

Explanation:

there is an explationation of this on a site called crash   course world history 1

the article must be ratified by three-fourths (38) of states within a proscribed deadline.

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