Post-test microscopy evaluations were performed on borosilicate (Borofloat® 33) and soda-lime (Starphire®) glass specimens following confined compression tests. These included optical and electron microscopy investigations of select specimens tested at low strain rates with confinement pressures up to 1 GPa. Specimens were evaluated following removal of the confinement sleeve or holder. The objective of this work was to investigate the flow and failure behavior of both glasses due to compressive loading with confinement. The observations provide an insight into the damage process that occurs during projectile impact/penetration into transparent armor. Highlights of the microscopy evaluations are compared and contrasted for the two glasses of interest. A damage mechanism is proposed based on comparison of the mechanical response data with the post-test microscopy findings.