Final answer:
The South seceded from the Union due to the threat to the slaveholding majority, sectionalism, and their belief in their right to self-governance as per the Declaration of Independence. The situation was complex and deeply rooted in preserving a social order based on the institution of slavery.
Step-by-step explanation:
The South seceded from the Union due to a variety of interrelated reasons. These reasons were primarily rooted in slavery, sectionalism, and their interpretation of the Declaration of Independence.
First, there was a threat to the slaveholding majority. For Southern states, slavery wasn't only a social institution; it was vital to their economy and way of life. The election of President Abraham Lincoln, who opposed the expansion of slavery, marked a significant threat to the South's socio-economic structure, prompting secession.
Secondly, sectionalism (the increasing socio-economic and political differences and tensions between the North and the South) was a major determinant of the southern disposition towards secession.
Finally, the South shifted its interpretation of the Declaration of Independence to evoke popular sovereignty, which they saw as their right to govern themselves and thus leave the Union.
However, I want to clarify that the analogy to, “images of the American colonies” throwing off King George’s rule doesn't hold much weight. The South's secession was far more complex, more steeped in preserving a social order that rested upon the institution of slavery.
Learn more about Secession