In this dissertation, we present work on the first-principles informed phenomenological modeling of the optical properties of materials. We use density functional theory and time-dependent density functional theory calculations to inform parameterized models of the response to light in materials. We include the effect of ultrafast nonequilibrium effects, as well as the importance of quantum mechanical lattice vibrations. Using these models, we validate the approaches, and predict the effect of both ultrafast phenomena as well as quantum mechanical vibrations on the optical properties of bulk and 2D materials. Such modeling opens up avenues for efficient phenomenological approaches to describing optical phenomena in materials while keeping the accuracy of first-principles simulations
