Political map of South American nations 22 June 1876 (Truncation of Paraguay): Following its defeat by Brazil and Argentina in 1870 (Paraguayan War), Paraguay remained under foreign occupation for over 6 years. The victorious allies stripped Paraguay of almost all its disputed territorial claims; the sole exception being the Gran Chaco, which Argentina largely conceded to Paraguay under pressure from the US and Brazil (Hayes Arbitration on Chaco) (a deal which did not, however, affect Bolivia's claim to the region (Chaco dispute)).