The authors report on x-ray absorption measurements performed on Zn1-xMnxO (x=0.05,0.25) at the Mn K edge (6539 eV) under high pressure. Mn is found to substitute for Zn both in the low pressure wurtzite phase and in the high pressure rocksalt phase. The Mn–O bond length is determined to be 2.02±0.01 Å at ambient conditions, with a compressibility similar to that of Zn–O in pure ZnO, being dictated by the ZnO crystalline environment. The phase transition is reversible in Zn0.95Mn0.05O, but not in Zn0.75Mn0.25O. The authors demonstrate that fluorescence detected x-ray absorption under high pressure can be used to characterize structural changes around minority elements.