Since I'm an American in Europe, I've been wondering if the average European of the mid-1800s had at least some notion of the current events during the Civil War. I know there was a telegraph link from North America to Britain at the time. Would it have been important news for Europeans? (i.e. would a business owner be concerned about losing shipments of something produced in the USA?)
Today the world is so interconnected that if a war breaks out anywhere, everyone will be following it intensely. But I know they had the technology to make relatively up-to-date news from another continent possible back then.
It would have been very important, as the war had pretty huge ramifications for European textiles, which was one of the largest industries at the time. http://en.wikipedia.org/wiki/Lancashire_Cotton_Famine
William Ewart Gladstone and other British politicians gave major speeches to British crowds about the war (most notably the speech in which he declared that the confederacy had "made a nation.")
The increased price in cotton led countries like Egypt to massively invest in cotton production. The subsequent drop in cotton prices when the south recovered, and the resulting failure of Egypt to meet its debts, was a direct cause of the British occupation of Egypt two decades later.
As far as European shipping goes, the Trent Affair was a major international incident, and the post-war "Alabama Claims" cost the British a huge sum of money in war in reparations.
France also followed the war as Napoleon III favored the confederacy, newspapers got in on the debate as well: http://en.wikipedia.org/wiki/France_in_the_American_Civil_War
So yes, they followed the news closely.
One of the most fascinating reads about the civil war written(And this is key, since its not hindsight 20/20 vision) as it unfolded is actually by two Europeans. You might have heard of them, they became a little bit famous a few decades later. Their names where Friedrich Engles and Karl Marx.
http://en.wikipedia.org/wiki/Writings_on_the_U.S._Civil_War
A Young Karl Marx was an European Corespondent for the New York Tribune and covered the Civil War extensively until he was fired for not promoting a quick peace between the states. In my opinion its a great read that is very in the present and it shows Marx's view as a Europeans view on the situation. And if you where wondering yes he was pro Union.
I don't know about other European countries, but it was covered very extensively and debated very heatedly in the UK. In general the British sided with the North on the moral issues but was heavily dependent on the South economically. There was one nearly divisive issue (the Trent Affair, where the Union intercepted a British ship to abduct two Confederates), and keeping the British in the Union fold was one of the outcomes of the Emancipation Proclamation. In the UK it was a hotly debated question, though, whether the outcome was worth the bloodshed.
There is a really lovely article on the correspondence between the Harvard botanist Asa Gray and the British naturalist Charles Darwin during the Civil War, which gives a great little perspective on it. Darwin starts out being very much pro-Union because he is a staunch abolitionist, but ends up (in part because he reads the British equivalent to Fox News, The Times, which was rabidly pro-South) thinking that maybe an independent Confederacy is necessary to stop the bloodshed. Once the Union wins pretends he was pro-Union the whole time and that ending slavery was worth any price. The citation: Ralph Colp, Jr., "Charles Darwin: Slavery and the American Civil War," Harvard Library Bulletin 266, no. 4 (1978), 471-489.
Thanks for the quick answers, guys! I'll make sure to have a look at the reading.