We report on terahertz (THz) emission from a single-layer ferromagnet, which involves the generation of backflow nonthermal charge current from the ferromagnet/dielectric interface by femtosecond laser excitation and subsequent conversion of the charge current to a transverse transient charge current via the anomalous Hall effect, thereby generating THz radiation. The THz emission can be either enhanced or suppressed or the polarity can be reversed by introducing a magnetization gradient in the thickness direction of the ferromagnet. Unlike spintronic THz emitters reported previously, it does not require an additional nonmagnetic layer or Rashba interface.