Social defence is an essential behaviour for social animals. It allows the existence of winners and losers in agonistic encounters, without deaths, promoting the group's stability. As for other aversive contexts, the environmental cues (e.g. the distance to the aggressor) are essential for a proper expression of defence. Understanding how the brain processes these cues, associating them with other stimuli and defining the defensive response, is a fundamental step towards a better comprehension of the neural bases of social defence. Previous work suggests that, in C57Bl/6 mice, a septo-hippocampal-hypothalamic circuit participates in the processing of environmental context and contributes to the organization of defensive behaviour. This pathway comprises the juxtadorsomedial region of the lateral hypothalamic area (LHAjd) and regions of the septo-hippocampal system, essential for the animal's self-location. Thus, our objective is to investigate the role of LHAjd in the processing of the environment during agonistic encounters. So far, we have observed that LHAjd activity is necessary for the proper expression of social defence, as its chemogenetic inhibition impairs the expression of active defence. Furthermore, we observed that LHAjd-projecting neurons in the subiculum (SUB) are active during social defeat, which can be a source of environmental cues to the hypothalamus. Our preliminary data on the optogenetic inhibition of the SUB > LHAjd corroborates this hypothesis since it also disrupts the expression of social defence. Taken together, our data suggests the existence of a hippocampal-hypothalamic circuit underlying the processing of environmental cues, essential to the execution of social defence.