The Crimean War springs to mind...
Conversely, to find anything comparable to the wars of the last century, you need to go straight back to Chengis Khan.
And - of course - there is the American Civil War. (You may say that it wasn't European, but most of Chengis Khan's wars weren't neither...)
I think he also forgot about the French Revolutionary and Napoleonic Wars, which were propelled by the quasi-religious fanaticism of the Jacobins as well as the ambition of Napoleon. It left France stunned, so that between 1815 and 1914 its population increased from 25 million to just 40 million, while Germany’s and Britain’s populations exploded. The War of 1914-1918 really demoralized the country. Casualties and property damage were relatively more than that than of the American Southland during the Civil War. And Yankees —and American blacks—don’t really appreciate how terrible the efects of that war were.