  We study the phase structure of four-dimensional N=1 super Yang-Mills
theories realized on D6-branes wrapping the RP^3 of a Z_2 orbifold of the
deformed conifold. The non-trivial fundamental group of RP^3 allows for the
gauge group to be broken to various product groups by Z_2 Wilson lines. We
study the classical moduli space of theories in various pictures related by
dualities including an M-theory lift. The quantum moduli space is analyzed in a
dual IIB theory, where a complex curve contained in the target space plays a
key role. We find that the quantum moduli space is made up of several branches,
characterized by the presence or absence of a low energy U(1) gauge symmetry,
which are connected at points of monopole condensation. The resulting picture
of the quantum moduli space shows how the various gauge theories with different
product gauge groups are connected to one another.
