This paper studies the problem of global decentralized control by output feedback for
large-scale uncertain systems whose subsystems are interconnected not only by their outputs but also
by their unmeasurable states. We show that under a linear growth condition, there is a decentralized
output feedback controller rendering the closed-loop system globally exponentially stable. This is
accomplished by extending an output feedback domination design that requires only limited information
about the nonlinear system. We will apply our design to lower, upper, and non-triangular
nonlinear systems. The significance of our results is that we do not need to have prior information
about the nonlinearities of the system. Furthermore, we need to only employ a linear observer in
combination with a linear controller to stabilize the system. A time-varying output feedback controller
is also constructed for use with large-scale systems that have unknown parameters.