  We show that the effective action that results from integrating out massive
Kaehler-Dirac fermions propagating on a curved three dimensional space is a
topological gravity theory of Chern-Simons type. In the presence of a domain
wall, massless, two dimensional Kaehler-Dirac fermions appear that are
localized to the wall. Potential gravitational anomalies arising for these
domain wall fermions are cancelled via anomaly inflow from the bulk
gravitational theory. We also study the invariance of the theory under large
gauge transformations. The analysis and conclusions generalize
straightforwardly to higher dimensions.
