On August 18, 1908 during the American regime, Mountain Province was established by the Philippine Commission with the enactment of "Act No. 1876". Ifugao, which was part of Nueva Vizcaya province, and the former Spanish "comandancias" of Amburayan, Apayao, Benguet, Bontoc, Kalinga and Lepanto, were annexed to the newly created province as sub-provinces. Amburayan was later abolished in 1920 and its corresponding territories were transferred to the provinces of Ilocos Sur and La Union. Lepanto was also reduced in size and its towns were integrated into the sub-provinces of Bontoc and Benguet, and to the province of Ilocos Sur.