Actually, the confederates did first invade Northern Territory. Fort sumpter. And Lincoln repeatedly assured them he wasn't after their slaves in states that had slaves prior to 1861
Ownership[edit]
Early in the nineteenth century, South Carolina had owned multiple forts, namely
Fort Moultrie,
Castle Pinckney, and
Fort Johnson, but ceded them, along with sites for the future erection of forts, to the United States in 1805.
[6]: 2 The forts were of questionable military value and costly to maintain, so when asked to cede them, the state complied.
[5]: 103 This was not the last time that South Carolina would cede forts to the United States; on December 17, 1836, South Carolina officially ceded all "right, title and, claim" to the site of Fort Sumter to the United States.
[6]: 4
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