Rivadavia was born in Buenos Aires on May 20, 1780, the fourth son of Benito Bernardino González de Rivadavia, a wealthy Spanish Lawyer, and his first wife María Josefa de Jesús Rodríguez de Rivadeneyra. On December 14, 1809, he married Juana del Pino y Vera Mujica, daughter of the viceroy of the Río de la Plata, Joaquín del Pino and his second wife, the vicereine Rafaela Francisca de Vera Mujica y López Pintado. His military appointment was rejected by Mariano Moreno.
Rivadavia was active in both the Argentine resistance to the British invasion of 1806 and in the May Revolution movement for Argentine Independence in 1810. In 1811, Rivadavia became the dominant member of the governing triumvirate as Secretary of the Treasury and Secretary of War. Until its fall in October 1812, this government focused on creating a strong central government, moderating relations with Spain, and organizing an army.
He was educated at the Royal College of San Carlos, but left without finishing his studies. During the British Invasions he served as Third Lieutenant of the Galicia Volunteers. He participated in the open Cabildo on May 22, 1810 voting for the deposition of the viceroy. He had a strong influence on the First Triumvirate and shortly after he served as Minister of Government and Foreign Affairs of the Province of Buenos Aires.
By 1814 the Spanish King Ferdinand VII had returned to the throne and started the Absolutist Restoration, which had grave consequences for the governments in the Americas. Manuel Belgrano and Rivadavia were sent to Europe to seek support for the United Provinces from both Spain and Britain. They sought to promote the crowning of Francisco de Paula, son of Charles IV of Spain, as regent of the United Provinces, but in the end he refused to act against the interests of the King of Spain. The diplomatic mission was a failure, both in Spain and in Britain. He visited France as well, and returned to Buenos Aires in 1821, at their friends' request.
In June 1821, he was named minister of government to Buenos Aires by governor Martín Rodríguez. Over the next five years, he exerted a strong influence, and focused heavily on improving the city of Buenos Aires, often at the expense of greater Argentina. To make the former look more European, Rivadavia constructed large avenues, schools, paved and lighted streets. He founded the University of Buenos Aires, as well as the Theatre, Geology, and Medicine Academies and the continent's first museum of natural science.
He persuaded the legislature to authorize a one-million pound loan for public works that were never undertaken. The provincial bonds were sold in London through the Baring Brothers Bank, local and Buenos Aires-based British traders also acting as financial intermediaries. The borrowed money was in turn lent to these businessmen, who never repaid it. Of the original million pounds the Buenos Aires government received only £552,700. The province's foreign debt was transferred to the nation in 1825, its final repayment being made in 1904.
His government had many problems, primarily an ongoing war with Brazil over territory in modern Uruguay and resistance from provincial authorities. Faced with the rising power of the Federalist Party and with several provinces in open revolt, Rivadavia submitted his resignation on June 27, 1827. He was succeeded by Vicente López y Planes. At first he returned to private life, but fled to exile in Europe in 1829.