Campo's successor was Miguel Santin del Castillo. This president's tenure of office was of short duration. In 1858 a coup d'etat of Barrios, then a senator, in which he was aided by the vice-president Guzman, his father-in-law, forced Santin to resign. Barrios subsequently obtained from the legislative assembly, sitting from January 17 to February 12, 1859, the sanction of his coup d'etat, as well as the constitutional amendments that he had not been able to carry through legally during Santin's rule, namely, to extend the presidential term from two to six years, and that of the deputies from two to four years.[XIV-59] The year 1859 was one of restlessness, engendered partly by the ungrounded fear of invasion by Santin's friends, who had taken refuge in neighboring states, and partly by Barrios' efforts to secure his own election to the presidency, in which he was successful. In August 1859 the existing disagreements between Salvador and Honduras, resulting from intrigues of refugees from the former, were brought to an end through the mediation of Guatemala.[XIV-60] [Sidenote: INVASION OF SANTA ANA.] The republic seemed to have attained a comparatively stable condition at the incoming of 1860. Barrios had been elected president, and recognized as such by the assembly.[XIV-61] He concluded in 1862 to hold diplomatic relations with the vice-president, who under the constitution of Honduras was entitled to occupy the executive chair of that state at the death of President Guardiola, and was favored by public opinion, although Carrera of Guatemala was upholding Medina, a usurper of the presidency. A treaty of alliance, both defensive and offensive, was entered into between Salvador and this vice-president,[XIV-62] which displeased Carrera; he demanded explanations, and they were given him.[XIV-63] The latter found an excuse to pick a quarrel with Barrios in the question with the Salvador clergy, who had been required to take an oath of allegiance to the government,[XIV-64] which they refused to do, Bishop Pineda y Zaldaña and a number of his subordinates repairing to Guatemala, where they were honorably received. Barrios was accused in the official journal of setting aside the conservative policy promised at his inauguration.[XIV-65] An expedition, under Colonel Saenz, believed to have been aided by Carrera, invaded Santa Ana at the cry of Viva la religion! Viva el obispo! and took the city, but were soon driven away by the citizens. Carrera disclaimed any connection with this affair. Some time after came Máximo Jerez, as minister of Nicaragua, proposing a plan of national union for Salvador, Honduras, and Nicaragua, with the intention of inviting Guatemala and Costa Rica to join them; but the project failed because of the refusal of Honduras to enter into the arrangement. Carrera had meantime dissuaded President Martinez of Nicaragua from the scheme.