of the Treaty of Velarde-Río Branco. This provided that two rivers (Yaravi and Yaverija) would compose most of the border for both countries. With Bolivia, The Treaty of Polo-Bustamante determined the partition of the Lake Titicaca and provided a much more accurate definition of the Peruvian-Bolivian border. This treaty also delimited the borders with Tacna (which was until then in Chilean control). When Leguía's term ended in 1912, he was succeeded by Guillermo Billinghurst, a millionaire businessman who had been the former mayor of Lima. During the following years, Leguía travelled in the United Kingdom and the United States, where he learned methods of banking and finance that he would later apply in Peru. During this time, Leguia was already in conflict with the Civilista Party and left its organization. Second presidential term In 1919, he again sought the presidency of Peru by trying to succeed José Pardo. Fearing that the former president's government along with the Civilist Parliament would not recognise his victory, he launched a successful military coup, which led Leguía to succeed Pardo as an interim president. He then proceeded to dissolve Congress and the new parliament elected him constitutional president of Peru. Leguía changed the Peruvian constitution (which had the longest continuance since 1860), and promulgated a new one in 1920, which was more liberal than its predecessor and provided more civil guarantees and unlimited reelections. Nevertheless, having himself promulgated the constitution, Augusto B. Leguía almost completely ignored it. The years of his tenure were marked with a dictatorial style of ruling by suppressing all opposition harshly. Although he represented the Peruvian oligarchy, the oligarchs revolted against him when he came to power, and it was his loyal supporters who installed him. Therefore he broke ties with the oligarchy, who protested his coup. Various political opponents of his government were exiled, of which the most prominent was Víctor Raúl Haya de la Torre, who while in exile in Mexico founded the American Popular Revolutionary Alliance (APRA) in 1924. It became one of modern Peru's most active and controversial political parties. Another important political figure that would emerge during this era was José Carlos Mariátegui, leader of the Communist Party of Peru. Among the positive initiatives that occurred during Leguía's second term was a program to modernize Lima by planning and starting public works through various loans. These included improving the health-care system by founding hospitals and