This study examined the relationships among distal (paternal and maternal family history of alcohol problems and violence) and proximal (general alcohol use, acute use associated with conflict incidents, alcohol-aggression expectancies) factors and physical aggression severity among 125 men and 125 women recruited from substance abuse treatment. Paternal alcohol problem history (PA) was related to alcohol-aggression expectancies, but no family history factors were related to general or acute alcohol use. Separate analyses examining predictors of aggression were conducted, one with general alcohol use and one with acute alcohol use. In both analyses, alcohol use and the maternal violence (MV) by PA interaction were significant. Specifically, MV was associated with aggression severity for those with a history of PA. The general alcohol use model also revealed significant alcohol by expectancy and MV by gender interactions. The findings suggest that expectancies are not the primary mediator of the alcohol-aggression relationship, alcohol use measurement issues may impact whether expectancies are observed to moderate the alcohol-aggression relationship, and that both maternal and paternal family history factors appear to impact aggression severity.