This longitudinal study tested whether associations between early attachment history and temperament and later anxiety symptoms are direct, or are indirect and explained by children's competencies in regulating emotions and relating to peers. Attachment patterns (secure, avoidant, preoccupied, disorganized) were assessed at 15 and 36 months, and temperament (negative emotionality-NE, Shyness) was ... [Show full abstract] assessed at 54 months. Peer competence (PC) and the ability to manage intense emotions were assessed at early school age, and anxiety symptoms in preadolescence. Both attachment history and temperament predicted anxiety. PC mediated the relations of security and disorganization with anxiety, and the ability to manage intense emotions mediated the relation between security and anxiety. PC also mediated the relations of NE and shyness with anxiety, and the ability to manage intense emotions mediated the relation of NE with anxiety. The findings highlight specific mechanisms that may contribute to the development of anxiety.