Because it all depended on what they believed in. If you believed in slavery you mostly fought for the south. If you thought that slavery was wrong you fought for the north.
The Union, or Northern side.
north
Confederates.
Confederates.
The Union.
Union (North)
The Union
they fought on the side of the south or confederates
If you are referring to the US Civil War, Germany played no part at all.
No. In 1936 Spain and Spain fought a war called the Spanish Civil War. A civil war is fought in a divided country, not between two countries. However, outside countries can support one side or the other in a civil war. Germany and Italy supported the Nationalist side in the Spanish Civil War, and the USSR supported the Loyalist side.,
The North, or the Union
Union.