For 10 points, name this country that incorporated most of the Provinces of the Rio de la Plata.
A writer from this country wrote about the "Tiger of the Plains" in a work arguing for civilization over barbarism. This country had a lengthy civil war between the Federalists and the Unitarian League. One leader of this country subjugated indigenous peoples in the Conquest of the Desert and established the  mazorca  police. The Congress of Tucumán declared the independence of this country, which was achieved in the May Revolution. President Juan (*)  Manuel de Rosas of this country was criticized in the nonfiction book  Facundo  by Domingo Sarmiento. While led by Bartolome Mitre, this country joined with Brazil and Uruguay to fight against Francisco Solano Lopez in the War of the Triple Alliance. For 10 points, name this country that incorporated most of the Provinces of the Rio de la Plata.
A writer from this country wrote about the "Tiger of the Plains" in a work arguing for civilization over barbarism.
Argentina  