Final answer:
The states of the Deep South that seceded were Mississippi, Florida, Alabama, Georgia, Louisiana, and Texas. They seceded swiftly after Lincoln's election due to their heavy reliance on slavery, which was a crucial part of their economy and social structure, in contrast to the Upper South and border states.
Step-by-step explanation:
The states in the Deep South that seceded from the Union were Mississippi, Florida, Alabama, Georgia, Louisiana, and Texas. These states seceded sooner than the states of the Upper South and the border states because slavery was more deeply entrenched in the Deep South. This region had larger numbers of both slaveholders and enslaved people, and as such, was more economically dependent on the institution of slavery. The Election of Lincoln and his anti-slavery platform acted as a catalyst, prompting states like South Carolina to call for secession conventions quickly.
Moreover, the Deep South was home to a greater commitment to the African slave trade, with some areas forcefully pushing freed black people back into bondage. This contrasted with the Upper South and border states, where Pro-Union sentiment remained stronger, likely due to smaller slaveholding populations. Following South Carolina's lead, other Deep South states declared secession, forming the Confederate States of America. The rapid secession of these states represented not only ideological differences but a serious economic divide predicated on the preservation of slavery.