The temperature dependences of helium solubility in potassium bromide crystals with different numbers of cationic defects, which were measured in the temperature range 400-720 K, exhibited solubility oscillations and contained three regions, in which an increase in solubility was followed by a solubility decrease. Each temperature dependence portion corresponding to an increase or decrease in solubility obeyed the Arrhenius equation. An anomalously low negative energy of solution of helium (-0.95 ± 0.1 eV) corresponded to the curve portions with a decrease in solubility, which was evidence of the chemical character of helium interactions with the environment in the crystal. The observed oscillations could be caused by the solution of helium in "free" cationic vacancies, which successively opened as a result of the dissociation of impurity-vacancy clusters. This mechanism of solution and the energy of solution were substantiated by additional studies of the dependence of helium solubility on saturation pressure (in the range 0.3-32 MPa). The anomalous value of the energy of solution could be caused by predominant interaction of helium with six bromine anions that formed the nearest environment of a helium atom in a cationic vacancy.