I have a big book of letters from American soldiers from every war and a lot of them definitely acknowledge the war was about slavery, as well as both sides not seeing the confederacy as Americans anymore. They even called going into confederate territory as going abroad.
A lot of those immigrants were communists and anarchists too based for Germany and were kicked out by Metternich during 1848.
Marx himself, even, was a firm support of the Unionist cause.
[off topic]
Seldom taught piece of US history.
The US Army recruited a lot of Irishmen fresh off the boat. They needed folks to fight in the Mexican War. When the troops got down to Mexico they decided they liked the Catholic Mexicans more than the Protestant Americans. St. Patrick’s Battalion fought for the Mexican side against the Americans.
Wasn’t the wargoal to end slavery added later to keep other powers from supporting the South?
Effectively, the war was always about slavery - the question, in the earliest stages, was whether the Union was fighting to contain slavery, or fighting to destroy it entirely.
