La Union (Ilocano: Probinsia ti La Union; Pangasinan: Luyag na La Union; Tagalog: Lalawigan ng La Union), is a province in the Philippines located in the Ilocos Region in the island of Luzon. Its capital is the city of San Fernando, which also serves as the regional center of the whole Ilocos Region.

The province is bordered by Ilocos Sur to the north, Benguet to the east, Pangasinan to the south and to the west by the shores of the South China Sea (West Philippine Sea).

La Unión, "The Union" in Spanish, was formed in 1850 when the Spanish colonial government of Governor-General Antonio Maria Blanco merged the three southern towns of Ilocos Sur province, the nine northern towns of Pangasinan, and the western towns of Benguet to the east (Eastern Pais del Igorotes in the Cordilleras). Pangasinenses were the majority in the new province because most towns had been in the province of Pangasinan.

On October 29, 1849, Governor General Claveria issued a promovido to fuse the Pangasinan-Ilocos-Cordillera areas into La Union. On March 2, 1850, Governor General Antonio Maria Blanco signed the Superior Decreto of La Union (34th province from Cebu-1565), with Captain Toribio Ruiz de la Escalera as the first Gobernador Military y Politico. Isabella II of Spain decreed the province's creation on April 18, 1854. In 1661, Andres Malong (Pangasinan) failed to recover La Union from the Spaniards after the Battle of Agoo. In 1896, the people of La Union began a revolt against the Spaniards, who had called La Union "Una Provincia Modelo" ("A Model Province"), led by Manuel Tinio Y Bondoc under Emilio Aguinaldo. The Americans collaborated with the Filipinos to end the Spanish.

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Wikipedia