e+A physics at a future Electron-Ion Collider

s = 63 158 (40 110) GeV/A for e+p (e+A) collisions. Whilst gluon distributions have been studied extensively in nucleons at HERA, there is very little information on them for x < 0.1 in nuclei. The rapid increase in the gluon momentum distribution at low-x in nucleons found at HERA, if not tamed, leads to the violation of the Froissart Unitarity Bound at small-x. This can be achieved in non-linear QCD by allowing for the recombination of low-x gluons until saturation of gluon densities occurs. Understanding saturation is an important goal not just for QCD in general, but also in understanding the initial conditions of heavy-ion collisions in particular. In this paper, I describe the physics that will be explored by e+A collisions, where saturation is more easily explored in this mode at an EIC than in e+p collisions due to the large nuclear densities achieved.