  We construct a weak coupling, many body theory to compute parton
distributions in large nuclei for $x\ll A^{-1/3}$. The wee partons are highly
coherent, non--Abelian Weizs\"{a}cker--Williams fields. Radiative corrections
to the classical results are discussed. The parton distributions for a single
nucleus provide the initial conditions for the dynamical evolution of matter
formed in ultrarelativistic nuclear collisions.
