When people talk about World War 1, it seems like the Monarchs are almost always left out, like they were not important to the war in any way. The causes and motivations are mentioned in the context of the country as a whole, i.e, "The Russians wanted to maintain influence in the Balkans" but never "The Czar wanted to maintain influence in the Balkans.
It seems like monarchs would not want to go to war with other parts of their family. The fact that they went to war makes it seem like: 1. they did not care, or 2. they did not have that much control over it.
I know the Reichstag (German legislature) voted to go to war but could Wilhelm II have stopped it, if he wanted, despite the Blank Cheque Agreement with Austria.
Edit: This seems like less of a /r/AskHistorians question and more of a /r/AskPeopleWhoKnowAboutOldUnusedConstitutions question but I don't think that exists.
In Barbara Tuchman's "The Guns of August" (I know it's a sketchy source, but I think better sources corroborate at least this part of her narrative), she actually talks about how Kaiser Wilhelm and Czar Nicolas exchanged some direct, personal telegrams on the eve of war, in an effort to somehow defuse the ticking time bomb. As we all now know, of course, their efforts failed.
In the end, by this time, the governments weren't really run by the monarchs; they were run by bureaucracies. Even the most absolute monarchs of the time has conceded significant power to parliaments and their equivalent to the German General Staff. Another passage from Tuchman that illustrates this point is how she describes the Kaiser in the first days of the war essentially wandering around with nothing to do; once he authorized the declarations of war, the machinery of the mobilization plans went to work and required little to no input. In fact, they were resistant to changes of any type (As conceived by their writers, of course; the degree to which the plans could have been modified on the spot is a matter of debate, but at the time the plans were seen by their creators as unchangeable. And my knowledge is mostly on the German plans, but I get the impression that other nations' plans were seen by their creators as similarly set in stone.)