...saw the opening engagement of the American Civil War-the bombardment of Fort Sumter in Charleston Harbor by Confederate artillery.
Civil wars, of course, impact nations at least as much if not more than wars with foreign powers, and ours was no exception.
I've had people ask 'Did the Civil War really impact world history all that much, and why do Americans keep the memories of it alive?' Now, this was a person from a nation (Australia) that had its own military 'coming-of-age' some 60 years later and, indeed, spends a day commemorating it.
My answer was, and would be 'Yes, it did impact many phases of world history, and the Civil War is for better or for worse a part of the national psyche along with Pearl Harbor and 9-11'.
The main cause wasn't as much about slavery as it was about states' rights. Up until the 1860s, the United States government wasn't much of a force in the average person's life. It was more of a weak federation of individual political entities. Most people had more loyalty to their home state than to some far-off government in a city the European powers considered something of a backwater village. The issue of slavery was still a festering sore that had been compromised on and put on the back burner for years. Eventually, perhaps, the issue would have been settled had there been mechanical tractors to do the work of slaves (Tractors don't need to eat when they don't work, after all-and they hadn't ever been known to revolt against their owners). I do think that slavery is an evil institution, but everyone that practiced it weren't all evil-it was what it was. But the issue was one that the major powers of Europe did away with long ago.
By the middle of the 19th century, there were differences in the economies and attitudes of the industrial and 'breadbasket' states of the North and Far West and the agricultural Southern states. The election of Abraham Lincoln brought a strong reaction from the southern states. Secession from the Union and the formation of the Confederate States of America, with a very limited central government, soon followed. The rest of the story you can read about virtually anywhere.
In the area of military history, the Civil War was a pivotal event. The beginning battles were fought much in the way Napoleon would have known-opposing skirmish lines a few yards apart, firing away at each other-and racking up vast body counts. The final campaigns of the war, around Richmond, saw the beginnings of the new horrors of trench warfare which would have been all too familiar to the soldiers at Verdun and Gallipoli. It was one of the first 'total', industrial wars, where the opposing population itself became a target. Rapid mass movement of troops by rail was pioneered. Aerial reconnaissance. Machine guns (albeit the primitive Gatling guns). Armored warships. Sherman's 'March to the Sea' in 1864 would be studied over the decades, and was in all probability the precursor to the 'Blitzkrieg' of World War II. And industrial power and mass logistics became at least as important, if not more so, than individual heroics and gallant soldiery.
The various world powers studied the conflict with interest. It was obvious that advancing technology was changing the nature of warfare. Also, the Powers had economic interests in America. Generally, Britain and France were inclined toward the Confederacy. Several incidents nearly brought both nations into the War, but adroit diplomacy, changing economic patterns, and some Union victories prevented any overt actions by those two empires. Russia leaned toward the Union, and Tsar Aleksandr sent warships to New York Harbor. It is possible that, had a few battles ended differently, there could have been a World War in the middle of the 19th Century.
Socially, the effects of 150 years ago still reverberate through the land. The inequality of the races has been lessened over the decades here in the US, but we've a way to go yet. Still, we've come far since the sad 'seperate but equal' (which wasn't, really) facilities once seen throughout the South. The power of the central government grew exponentially during the Civil War-necessary, of course, to provide the coordination of a large nation at war-and to this day is a far more powerful entity than the original Founding Fathers envisioned. Certainly, the 'Wild West' made famous in so many films and books wouldn't have been so wild without all those old Civil War vets of both sides either looking for adventure or psychologically scarred or embittered at the outcome-or a combination of all three-turning to outlawry.
After the Civil War, the United States took the first steps toward becoming a genuine world power, not so much in the military sphere as the economic one. The United States became an industrial and agricultural powerhouse in the second half of the 19th Century.
Finally, the Civil War did influence the formation of several nations, primarily Canada and Australia. Both nations studied the war and the government that arose during and afterward. Canadians went toward the concept of a stronger federation, as their fathers felt that the pre-war State governments probably had too much power and there was too much democracy in their southern neighbors. Peace and order would be their watchwords. The founders of the Australian Federation, conversely, leaned toward a weaker executive, fearing too strong a central government, and prohibited the importation of 'coloured labour' in part to prevent the formation of a society based upon slavery.
So, did the American Civil War impact world history? Of course. I didn't have to do much research to come up with this post. I'm quite sure many teachers and historians could expound ad infinitum, ad nauseum on the subject.