Marx sent a letter to Lincoln, and Lincoln's staff responded via Ambassador Adams. It's a really interesting moment in history that's been buried by US Red Scare ideology.

from wiki on Adams:

Part of his duties included corresponding with British civilians, including Karl Marx and the International Workingmen's Association.[7] Adams and his son, Henry Adams, who served as his private secretary

https://www.marxists.org/archive/marx/iwma/documents/1864/lincoln-letter.htm

[–] Asafum@feddit.nl 13 points 1 year ago* (last edited 1 year ago)

Oh man that would be a fun tidbit for conservatives when they try the old "accckshully Lincoln was a Republican who fought to free slaves so it's the Democrats that are the racists!"

"Ok, so how do you feel about Lincoln working with Karl Marx, you know, Mr.Communisim?"