They launched a movement to secede from the Union
south had lost its influence in the national politics
You forgot to list "the following individuals," but the answer is Abraham Lincoln.
Because President Abraham Lincoln had won without getting a single vote from the southern states.
election of 1860
The Freeport Doctrine affected the outcome of the election of 1860 in many ways. When it was initially created, many citizens liked it and agreed, but not the Southerners. They disagreed and did not like the Doctrine, which cost Douglas, the creator, his potential presidency.
The election of 1860 angered Southerners primarily because Abraham Lincoln, a candidate from the anti-slavery Republican Party, won without securing a single electoral vote from the South. This outcome signified the diminishing political power of slaveholding states and heightened fears that Lincoln’s presidency would threaten their way of life and the institution of slavery. Many Southerners perceived his election as a direct attack on their rights and interests, leading to a sense of disenfranchisement and ultimately contributing to the secession of Southern states from the Union.
in 1860
Because was campaigning on a ticket of no new slave-states. When he won the 1860 election, it meant that the South would always be outvoted in Congress.
Lincoln winning the 1860 election on a ticket of no new slave-states. It meant that the South would always be outvoted in Congress if they stayed in the USA.
Lincoln's opponent in the 1860 election
Tuesday, November 6, 1860
November 1860