Following his father's death in 1032, Harun was effectively made governor of Khwarazm by the Ghaznavid sultan Mas'ud. The title of Khwarazm-Shah was not given to him, but to Mas'ud's son Sa'id; Mas'ud had been distrustful of Altun Tash and probably wanted to avoid giving his son too much power.
Following his father's death in 1032, Harun was effectively made governor of Khwarazm by the Ghaznavid sultan Mas'ud. The title of Khwarazm-Shah was not given to him, but to Mas'ud's son Sa'id; Mas'ud had been distrustful of Altun Tash and probably wanted to avoid giving his son too much power.