In this paper we revisit and prove optimal order and mesh-independent convergence of an inexact Newton method where the linear Jacobian systems are solved with multigrid techniques. This convergence is shown using Banach spaces and the norm, max{ • 1 , • 0,∞ }, a stronger norm than is used in previous work. These results are valid for a class of second order, semi-linear, finite element, elliptic problems posed on quasi-uniform grids. Numerical results are given which validate the theory.