The most striking feature of this order is that it occurs at such accessible temperatures. The shortest through space distance between Cr atoms is d = 8.32 Å, and the shortest throughbond distance is d = 15.1 Å, and occurs through 8-bond superexchange, Cr-N-C-S-Bi-S-C-N-Cr. This can be compared to the iron cyanide Prussian Blue, which orders ferromagnetically at 5.6(1) K with the magnetic Fe 3+ ions separated by 7.2 Å, where magnetic superexchange occurs through a six-bond Fe 3+ -N-C-Fe 2+ -C-N-Fe 3+ pathway 10.2 Å long. In Prussian Blue, charge and spin delocalisation onto Fe 2+ (approximately 5% of an electron) through a mixed-valence mechanism are critical to the generation of long-range order. Mixed valency is not likely in this case as the adjacent oxidation states for both Cr and Bi are not easily accessible, and the antiferromagnetic interactions we observe rule out the ferromagnetic 'double exchange' found in Prussian Blue. On possible explanation would be facilitation of this comparatively strong superexchange through the accessible NCS redox states-as can be see in the relatively dispersive conduction band in our previously reported DFT bandstructure calculations of Cr[Bi(SCN) 6 ]. The importance of effective superexchange can be seen by comparison to paramagnetic salts of Cr 3+ , e.g. [Cr(CN) 6 ][Co(NH 3 ) 6 ], where |θ | < 0.05 K and d Cr-Cr = 7.4 Å. These comparisons also allow us to eliminate through-space dipolar coupling as a significant contributor to the observed order. Indeed, even in molecular cluster nanomagnets with similar magnet-magnet spacing but much larger total spin it is clear that superexchange rather than dipolar order drives the transition to magnetic long-range order, e.g. the S = 35/2 The Cr ions form a face-centered cubic lattice, with only small chemical differences between different crystallographic directions. The interactions are likely to be primarily through-bond rather than through space, and as such the nearest neighbour (J 1 ) and next nearest neighbour (J 2 ) interactions are likely to be comparable in magnitude [Fig. ]. This is directly analogous to what has been found in both rocksalt transition metal monoxides, e.g. the canonical MnO, and the oxide double perovskites . The {111} cubic AFM order observed (Type II) occurs for J 2 > 0.5J 1 for an ideal J 1 -J 2 face-centered cubic magnet with antiferromagnetic interactions. The combination of this with the observed mild frustration, |θ |/T N = 1.9, and the presumed weakness of both further-neighbour superexchange (due to the long distances) and of non-Heisenberg effects due to the Cr 3+ ion presence suggests that suggests that J 2 < J 1 , and thus that a small (20%) reduction in J 1 /J 2 might induce a transition into a highly frustrated state. Like other perovskites, Cr[Bi(SCN) 6 ] has a wide-range of potential chemical possibilities for tuning its magnetic function: not only through substitution of the magnetic Cr, but also of the non-magnetic Bi, and the inclusion of A-site cations . This, together with the moderate exchange strength found in this material, comparable with the Zeeman splitting accessible through superconducting magnets, suggests that NCS double pervoskites are ideal platforms to engineer the complex, chiral, multi-k magnetic orderings of current interest for their potential use in magnetic computation.