So, a large portion of a project I've been working on involves international diplomacy. The opening chapter involves a scene of storming an embassy.

I was wondering if there's any sources on diplomacy from a bit earlier in history? Like Roman Empire/China/Middle Ages kind of stuff I can look at? Well known incidents, maybe?

In general, do people think diplomatic issues could make for an interesting fantasy story?

Does anybody have some recommendations for good fantasy involving diplomatic issues heavily?