In this study, rolled and solutionized magnesium alloy with 6% of aluminum (A6) is characterized under varying strain rates (10^-4-10^6 /s) and pressures up to 10 GPa. Low ( ~ 0.001 /s) to high strain rate (~10^3 /s) experiments are conducted in a universal compression machine and conventional split Hopkinson bar respectively. Additionally, the effect of pressures and very high strain rates on strength behavior of A6 is investigated using the pressure shear plate experiments (PSPI). In PSPI experiments the normal stress is aligned normal to the rolling direction and the shearing is performed along the rolling direction. The pressure and strain rates in the sample are varied by changing impact velocities and using appropriate anvil materials. A complete stress-strain behavior of the material in PSPI experiments are extracted using the newly developed hybrid simulation-based method to incorporate the plasticity of the anvils. In addition, the possible deformation mechanisms involved at different strain rates and pressures are discussed.