In the state of Bolivar, the liberal insurrectionists triumphed, while in Santander the conservatives themselves started a revolution which Ospina only succeeded in suppressing by the bloody battle of Oratorio. Meanwhile Mosquera had become governor of Cauca, and when the conservatives of that state tried to expel him, he beat them and took advantage of his victory to declare himself independent of Ospina. The latter advanced, but Mosquera defeated him, and invaded the upper Magdalena, gaining the battle of Segovia. In every state there was an insurrection against Ospina, and three ex-presidents accompanied the insurgent armies. On the surface the civil war appeared to be a mere contest for personal power between Mosquera and Ospina, but the former had ensured a large support by raising the banner of federalism, and the latter's triumph would probably have meant a strengthening of the national government and certainly a reaction from the radicalism which had gained ground year by year since the fall of Bolivar. Supported by the clericals, conservatives, and reactionists, Ospina fought tenaciously and with a fair prospect of success. But the federalist armies advanced relentlessly from both north and south, and one after another the provinces of the eastern plateaux were wrested from him by bloody and well-contested battles. Bogotá was finally taken and the president imprisoned, but Mosquera's opponents kept up the conflict for some time in the states of Panama, Santander, and Antioquia, and it was near the end of 1861 before the federalists were everywhere triumphant.
With Mosquera at the head of affairs, under the title of "Supreme Director," a congress was summoned whose members were called, not deputies, representatives, or delegates, but "plenipotentiaries" of the sovereign states. This congress adopted a new constitution, New Granada's sixth since 1830. The triumphant liberals expelled the Jesuits, abolished ecclesiastical entails, extinguished the monastic orders, confiscated Church property, decreed the absolute separation of Church and State, imprisoned the archbishop, and secularised the schools. Suffrage was made nominally universal, and the death penalty abolished. The name of the country was changed to the "United States of Colombia," and it became little more than a league of nine federal states for the purpose of defence against foreign attack. The national government was expressly prohibited from interfering in the affairs of the states, even for the preservation of order, and a clause of the Constitution provided that "when one sovereign state of the union shall be at war with another, or the citizens of any state shall be at war among themselves, the national government is obligated to preserve the strictest neutrality." The federal judiciary had no power to decide any constitutional questions nor could its decisions bind the state authorities. The national government was deprived of half its revenue for the benefit of the states, and the receipts of the latter equalled the federal income. This Constitution remained in force for twenty-two years, during which civil wars and factional disputes continually racked Colombia.