They didn't.
Missouri suffered guerrilla war throughout the conflict, but did not secede.
Kentucky was allowed to remain neutral at the beginning, and then voted against secession. An alternative Confederate government was set up there when Bragg invaded, but it collapsed when he retreated.
Maryland probably would have seceded, had not Lincoln (illegally) jailed its pro-Confederate leaders.
no Kentucky, Maryland, Missouri, and Delaware did not succeed
they didnt
Kentucky, Missouri, Maryland, Delaware.
Missouri, Kentucky, West Virginia, Delaware, and Maryland.
All the non-slave states, plus four slave-states that did not vote Confederate - Kentucky, Missouri, Maryland, Delaware.
Borders do not secede but states do. Kentucky, Maryland and Missouri were border states that did not secede in the union.
Delaware Kentucky Missouri Maryland
no Kentucky, Maryland, Missouri, and Delaware did not succeed
Delaware, Maryland, Missouri, and Kentucky.
they didnt
Kentucky, Missouri, Maryland, Delaware.
Kentucky, Missouri, Maryland, Delaware.
The states that DID NOT secede from the Union was Delaware, Maryland, Kentucky, and Missouri. These four states did not secede from the Union because They were Border states, meaning they were between the Union and the Confederacy.
Missouri, Kentucky, West Virginia, Maryland and Delaware
Missouri, Kentucky, West Virginia, Maryland and Delaware
Missouri, Delaware, Maryland, Kentucky, and West Virginia.
Missouri, Kentucky, West Virginia, Delaware, and Maryland.