  Chamseddine and Mukhanov showed that gravity and gauge theories could be
unified in one geometric construction provided that a metricity condition is
imposed on the vielbein. In this paper we are going to show that by enlarging
the gauge group we are able to unify Chern-Simons gauge theory and Chern-Simons
gravity in 3-D space-time. Such unification leads to the quantization of the
coefficients for both Chern-Simons terms for compact groups but not for
non-compact groups. Moreover, it leads to a topological invariant quantity of
the 3 dimensional space-time manifold on which they are defined.
