 Abra last formed part of the province's representation in 1919.The first district of Ilocos Sur is among the original representative districts from 1907 which has never changed in territorial coverage, along with Albay's first, Ilocos Norte's first and second, and Iloilo's first districts.Ilocos Sur, which at the time included the sub-province of Abra, was initially divided in 1907 into three representative districts.