Tacna is one of the twenty-four departments that, together with the Constitutional Province of Callao, form the Republic of Peru. Its capital is Tacna. It is located in the extreme south of the country, bordering Moquegua to the north, Puno to the northwest, Bolivia to the east, Chile to the south, and the Pacific Ocean to the west. With 16 076 km² it is the fourth least extensive department, ahead of Moquegua, Lambayeque and Tumbes, the least extensive. It was founded on June 25,1875. It comprises in two-thirds of its space one of the driest portions of the coastal desert crossed by narrow rivers.
And the remaining third corresponds to the Andean puna, an elevated portion of the rugged Andes mountain range south of the Collao Plateau. It was populated by hunter-gatherers at the beginning of the Holocene and its culture was influenced by the Altiplano peoples. During the Colony, its population was immersed in the process of miscegenation. In the nineteenth century, in this region several secessionist uprisings took place prior to the Independence of Peru. After the War of the Pacific, it was administered mostly by Chile, Tarata until September 1,1925 and the rest until August 28,1929 due to the Treaty of Lima. The current province of Jorge Basadre and Candarave, north of the Sama River continued to be administered by Peru after the Pacific War. More than seven-eighths of the Tacna population live in the departmental capital.
The traditional culture has an important Aymara cultural substrate, especially in the high Andean and Creole areas. The resistance to post-war Chileanization has been an important part of the region's identity.