Trade unionists and socialists gathered in London to establish the First International, launching an organized transnational labor movement with Karl Marx among its architects.

Workers and radicals from across Europe met in London and founded the International Workingmen's Association, later shaped decisively by Karl Marx.

Abraham Lincoln won a second presidential term over Democrat George McClellan, a victory that ensured the Union would fight the Civil War to its conclusion.

Union General William Tecumseh Sherman set fire to Atlanta and marched 62,000 troops toward Savannah, waging total war on the Confederate heartland.