The first representatives of 4H (BaMnO3-type structure, P6(3)/mmc, Z = 4) and 9R (BaMnO3-type structure, R(3) over bar $m, Z = 9) inverse Perovskite phases are presented. The phases are obtained within the solid solutions (Sr3-xBaxN)E with E = Bi, Sb. The crystal structures and homogeneity ranges were studied by combined X-ray and neutron diffraction as well as chemical analyses. The cubic Perovskite phase with Bi (Sb) is stable in the range of 0.00 <= x <= 0.90(5) (0.00 <= x <= 1.30(5)), the 4H variant is stable for 1.55(5) <= x <= 2.10(5) (1.85(5) <= x <= 2.45(5)), the 9R structure is stable for 2.50(2) <= x <= 2.55(2) (2.56(2) <= x <= 2.60(2)), and the 2H phase is stable for 2.75(5) <= x <= 3.00 (2.80(5) <= x <= 3.00). Ba occupies preferable sites in the hexagonal stacking of close packed layers of alkaline earth metal ions and E3-; Sr is mainly located in cubic stacked layers. The phase order upon going from cubic (Sr3N)E to 2H-type (Ba3N)E concomitant to the pronounced Sr/Ba partial order can, in general, be rationalized considering the Coulomb repulsion of nitride ions, as well as the size and charge density of the alkaline earth metal ions.