The ventrolateral part of the ventromedial hypothalamus (VMHvl) is central for driving aggression. This study investigated changes in the aggression circuit over repeated winning in male mice. First aggressive behaviors were characterized in short-term and long-term winners and then synaptic and cellular changes in the VMHvl were investigated over repeated winning. Repeated resident-intruder (RI) tests were used to provide winning experiences to the test mice. During the test, a non-aggressive group-housed male mouse was introduced into the home cage of a single-housed male mouse for 10 minutes. If the resident male attacked the intruder and the intruder showed flight and submissive postures, the resident mouse was considered aggressive and won. If the resident mouse investigated the intruder but did not attack during the 10 minutes, the resident was considered non-aggressive and underwent social interaction. Only animals that consistently attacked and won across days were included in the final analysis. The dataset includes fiber photometry, behavior annotation, and in vivo and in vitro electrophysiological recording data.