I'm not aware of anything exactly like what you have in mind, but here are a few things which might be close. They all take aim at the widespread belief that the intellectual development of mathematics takes place independently of any extra-mathematical philosophical beliefs. Perhaps not surprisingly, the examples below have to do with infinity in one way or another.
You mentioned Leibniz. Leibniz on Mathematics and the Actually Infinite Division of Matter by Samuel Levy argues that Leibniz developed his novel ideas in mathematics and metaphysics in concert.
Georg Cantor:His Mathematics and Philosophy of the Infinite by Joseph Dauben describes the close relationship between Cantor's philosophical and mathematical beliefs.
The book Naming Infinity by Loren Graham and Jean-Michel Kantor make an intriguing argument that the pioneers of descriptive set theory were strongly influenced by their belief in name-worshipping.