The atttitude of the South concerning slavery remained constant from early colonial days to the beginning of the Civil War whereas the attitude of the North underwent various alterations. The majority of Southerners supported the institution of slavery, and continued to support it when the North decided to condemn it. On the other hand, the North was indifferent to slavery when it was first instituted. Through a gradual process, the Northern people were persuaded to believe that it was evil. It was not until nearer the war that the entirety of the North had rallied behind the abolitionist cause.
The South's feelings about slavery were the same from beginning to end. Slavery was a necessary evil in the South. Slaves were the main source of cheap, reliable labor. Many of the Southerners looked down upon slaves, and did not want them to be freed. They justified their choice by claiming that freed slaves would have a worse life in the North or Africa than as a slave in bondage. From the 1820's to the 1860's the government was primarily dominated by Democrats, which were mainly Southerners, making it much easier for slavery to continue on in the United States. .
The North, However went through various alterations in their view of slavery. At first the North was not concerned with the South's actions, later they became increasingly concerned with slavery due to moral convictions, lastly political issues split the two regions, and slavery was an easy target.
Originally Slavery was of no concern to the North. They worried little about their southern neighbors. Early on, the North was focused on itself. Industrialization and foreign policy dominated the North's attentions. Slavery was viewed as inconsequential in a time of development.
Slavery came under fire when times of enlightenment emerged. Bible-beaters and evangelists demanded change. At this time it was still not the majority of the Northerners intent to abolish slavery, but the abolitionist movement was gaining momentum.