Weat Virginia Delaware, Maryland, Missouri, and Kentucky were five slave states that did not secede the Union, and the were were called border states.
In the US Civil War, the union meant the United States and its capital remained in Washington, DC.
THE UNION WAS A SIDE IT STANDS FOR THE NORTHERN STATES THAT REMAINED LOYAL TO THE ORIGINAL UNITED STATES. THE TERM UNION IN THIS CASE IS THE UNION OF STATES IT IS A NICK NAME FOR THE U.S.
The Union was the name given to the states that remained loyal in the Civil War. Before the war, these had no special significance as a group. All states simply belonged to the USA.
Romania, Slovakia, Austria and Slovenia are all members of the European Union and all border Hungary.
During The American Civil War, Northern states were called The Union as they remained in The UnitedStates of America.
Two examples are Austria and Slovakia.
John Bell.
border states
Those were known as the Border States.
During the American Civil War there were five states which stayed neutral and were given the name "border" states. They were called border states because they each bordered a free state and were aligned with the union. The five border states were Delaware, Kentucky, Maryland, Missouri, and West Virginia.
Delaware remained loyal to the Union. Maryland might have seceded had Lincoln not placed Federal troops around the state legislature, but the state remained in the Union. Kentucky did not secede but could not entirely be said to be loyal to the Union. It was officially neutral. About twice as many regiments from Kentucky joined the Confederacy as joined the Union, but it is likely that some Kentucky men joined with regiments from other states both north and south. Missouri was a slave state and never formally seceded. Although support for the South was strong, and a pro-Confederacy Army and legislature formed, the state remained in the Union. Estimates of the time say that Missouri was 90% for the Confederacy and 10% Union. The last one to name here was West Virginia, which was part of Virginia until several counties banded together to secede from Virginia to rejoin the Union as a new state in 1863. West Virginia never existed as a slave state, having been brought into the Union after the Emancipation Proclamation, and is therefore a tricky but incorrect answer to this question.