In this paper, characteristics of turbulent combustion and NO_x emission for high hydrogen-content fuel gases (H₂ > 70 vol. %; "hydrogen-rich") are addressed. An experimental investigation is performed in a perfectly-premixed axial-dump combustor under gas turbine relevant conditions. Fundamental features of turbulent combustion for these mixtures are evaluated based on OH-PLIF diagnostics. On the other hand, NO _x emissions are measured with an exhaust gas sampling probe positioned downstream the combustor outlet. Compared to syngas mixtures (H ₂ + CO), the operational limits for hydrogen-rich fuel gases are found to occur at even leaner conditions concerning flashback phenomena. With respect to effects of operating pressure, a strongly reduced operational envelope is observed at elevated pressure. Only with decreasing the preheat temperature a viable approach to further extend the operational range is seen. Evaluation of the averaged turbulent flame shape shows that the profile of the flame front is generally approaching that of an ideal cone. Thus a simplified approach for estimating the turbulent flame speed via the location of the flame tip alone can be applied. The level of NO_x emission for the hydrogen-rich fuel mixtures is generally above that of syngas mixtures, which exhibit already higher NO_x emission values than natural gas. Distinct chemical kinetic features are found specifically at elevated pressure. While the pressure effects are weak for syngas, a non-monotonic behavior is observed for the hydrogen-rich fuels. Reaction path analysis is performed to complement and provide more insight to the findings from the measurements. From chemical kinetic calculations a distinct shift in NO_x formation pathways (thermal NO_x vs. NO_x through N₂O/NNH reaction channels) can be observed for the different fuel mixtures at different pressure levels.