Mainstream theorizing of paedophilia from the mid-1920s through to mid-1960, and even into the 1980s, was importantly psychodynamically oriented. The early history of the concept of paedophilia in early psychodynamic thought is problematic, however. Extant historical references are not without problems of their own, and have suffered from a lack of insight in the wider history of sexuality at this point of ‘erotic age preferences’. Review of primary sources highlights several contemporaneous interfaces of early psychodynamic theory: with the established forensic psychology of perpetrators of child sexual abuse; Krafft-Ebing's specific aetiological concept of age fetishism; early study and typologies of homosexual age preferences; emergent and divergent ideas about psychosexual infantilism; and strikingly late empirical attention to the psychiatry of the perpetrator of intergenerational incest.