Does knowledge and study of history support your religiosity or diminish it?

I think that this is likely to be as varied as people's religiosity in general.

From my perspective, I was born and raised Catholic. I remain so. Partly that is despite my study of history. In the two subjects referenced in my flair--WWII and the Spanish Civil War--there are a number of Catholics that did truly horrendous things. Sometimes they used their religion to justify these crimes, which sickens me. Since it's an unpleasant subject, let's not dwell on it further.

I have also been influenced by other accounts, such as those of anticlerical violence in Spain during that country's civil war. I could--and have--focused on the criminal nature of violence against these noncombatants. That kind of cruelty is also abhorrent to me, but it is also unpleasant. Let's move on.

For me, for my faith, I focus on the example of priests risking their very lives to bring the Sacraments to people during the Spanish Civil War, and on Fr. Maximilian Kolbe and others who first resisted the Nazi regime and later sacrificed themselves for others, and on those who rescued Jews in the hierarchy like Cardinal Roncalli and in the priesthood like Père Marie-Benoît to many in the laity as well, and many heroic chaplains that risked their lives to bring comfort to suffering soldiers and civilians. I could focus on the other stuff--and I am sure some do--but I think the stories of heroism speak more loudly than the stories of criminality and barbarism. It also reminds me that regardless of how rough life can be sometimes, I don't literally have a gun to my head having to make a decision. That perspective can be helpful sometimes.