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We present spectroscopic data for 180 red giant branch stars in the isolateddwarf irregular galaxy WLM. Observations of the Calcium II triplet lines inspectra of RGB stars covering the entire galaxy were obtained with FORS2 at theVLT and DEIMOS on Keck II allowing us to derive velocities, metallicities, andages for the stars. With accompanying photometric and radio data we havemeasured the structural parameters of the stellar and gaseous populations overthe full galaxy. The stellar populations show an intrinsically thickconfiguration with $0.39 \leq q_{0} \leq 0.57$. The stellar rotation in WLM ismeasured to be $17 \pm 1$ km s$^{-1}$, however the ratio of rotation topressure support for the stars is $V/\sigma \sim 1$, in contrast to the gaswhose ratio is seven times larger. This, along with the structural data andalignment of the kinematic and photometric axes, suggests we are viewing WLM asa highly inclined oblate spheroid. Stellar rotation curves, corrected forasymmetric drift, are used to compute a dynamical mass of $4.3\pm0.3\times10^{8} $M$_{\odot}$ at the half light radius ($r_{h} = 1656 \pm 49$pc). The stellar velocity dispersion increases with stellar age in a mannerconsistent with giant molecular cloud and substructure interactions producingthe heating in WLM. Coupled with WLM's isolation, this suggests that theextended vertical structure of its stellar and gaseous components and increasein stellar velocity dispersion with age are due to internal feedback, ratherthan tidally driven evolution. These represent some of the first observationalresults from an isolated Local Group dwarf galaxy which can offer importantconstraints on how strongly internal feedback and secular processes modulate SFand dynamical evolution in low mass isolated objects.

The Resolved Structure and Dynamics of an Isolated Dwarf Galaxy: A VLT and Keck Spectroscopic Survey of WLM