In the first half of the nineteenth century there was no dispute between Bolivia and Paraguay concerning the Chaco. During the long dictatorship of Francia, her first President, from 1811, when Spanish rule came to an end, down to 1840, Paraguay existed in a state of complete isolation and deliberately held aloof from the outside world. After Francia’s death, the Congress, assembled at Asunción, approved in 1842 the Act of Independence of the Republic. The communication of this act to foreign countries marks the recognition of the independence of Paraguay, who concluded with the Argentine in 1852 a Frontier and Navigation Treaty, Article 4 of which specifies that the “River Paraguay shall belong from bank to bank in full sovereignty to the Republic of Paraguay down to its confluence with the Paraná.”