Your question mentions references in Shakespeare. The other work I know of from before 1800 that mentions it a fair bit is Voltaire's Candide. It is mostly a satirical send-up of the philosophy that this is "the best of all possible worlds". But in the process of burning that idea to cinders, war rape is invoked at least twice that I can remember. I believe the phrase that was used was "fulfilling the natural urges of soldiers", the implication being that this phrase was being used to justify it.

Given that this was a satire of those views, I think its quite fair to say that Voltaire (and presumably his intended audience) viewed it as an evil, along with the various murders, starvations, slavery, mutilations, etc. that occurred in that story.

Your question mentions references in Shakespeare. The other work I know of from before 1800 that mentions it a fair bit is Voltaire's Candide. It is mostly a satirical send-up of the philosophy that this is "the best of all possible worlds". But in the process of burning that idea to cinders, war rape is invoked at least twice that I can remember. I believe the phrase that was used was "fulfilling the natural urges of soldiers", the implication being that this phrase was being used to justify it.

Given that this was a satire of those views, I think its quite fair to say that Voltaire (and presumably his intended audience) viewed it as an endemic evil in the world, along with the various murders, starvations, slavery, mutilations, etc. that were related in that story.