None. All other countries proclaimed neutrality. The North's actions towards a British ship that was bringing Confederate diplomats to Europe to request the recognition of the CSA as a country came close to bringing England into the conflict.
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.,
They had civil wars supported by foreign countries.
Hessians supported Britain while France supported the Patriots.
Actually there was never any real involvement of other countries in the American Civil War. Great Britain did lean toward the South for a period due to economic reason and the cotton trade. But, once the war started going against the South after Gettysburg, they refused support all together.
No, it wasn't like any other countries had any involvement in France's civil war, like fighting against Spain and Russia and other countries, and it's not like the British tried to get into our civil war because it was about succession, not slaves. No, no other countries are ever involved in another country's civil war, like, hmmm, Iraq?
Soviet Union supported Communist China and nearly all the other powers supported Nationalist China.
One one side were the Spanish Republic, supported by the Soviet Union, Socialist volunteers from various other countries as well as some Spanish Trade Unions. On the other, winning side, were Nationalist Spain, under Francisco Franco. They were supported by the fascist countries of Germany, Italy and Portugal.
The Republicans, or Loyalists were communists supported by the USSR. Volunteers from other countries also fought for the Republicans, including a brigade from the US. The Nationalists were fascists supported by Italy and Germany. The Spanish Foreign Legion also cast its lot with Franco and the Nationalists, and as the name implies they were volunteers from different countries.
Costa Rica has had a civil war, but never a war with other countries.
Roundheads.
During the English civil war, those who supported the monarch were called puritans.
An Abolitionist supported the abolition or end of slavery during the US Civil War.