Answer:
Some of the factors that contributed to emphasise among anti slavery activists on gradual emancipation were Religious, Abolitionist movement and the Civil War
Explanation:
It was all connected and one thing led to the other.
From around 1830 to 1870 The Abolitionist movement took pace. Most of abolitionist were religious people inspired by the concept of men being equal in the eyes of god. This moral ideals were what determined abolitionists to fight against slavery. They passed laws and run for important government positions to bring emancipation and antislavery politics into the agenda. Some abolitionist worked writing articles and novels bringing awareness to the public and a change of thought in the society, others helping slaves to escape into the North. It was a hard and long work they had ahead. Some of the most famous abolitionists were William Lloyd Garrison, Susan B. Anthony, Frederick Douglass, Harriet Beecher Stowe, John Brown, Harriet Tubman, Sojourner Truth and Elijah Lovejoy. Most of them contributed to the cause fighting and defending not only anti-slavery but also women's rights. Some of them like Harriet Tubman and Frederick Douglass were once slaves themselves.
This movement caused a huge opposition in the pro-slave states from the South, which prohibited abolitionism.
This division between northern and southern states led of course to The Civil War in 1861. President Abraham Lincoln, was against slavery and led the Emancipation Proclamation in 1863 which freed all slaves. The Thirteenth Amendment was finally constitutionalized in 1865, abolishing all forms of slavery in United States.
The Abolitionist movement came to an end once the Fifteenth Amendment in 1870 was proclaimed, which gave voting right to black man.