Little is known about the first years of the life of Rafael Núñez. It is known that he served as Judge of the circuit of Chiriquí, Panama in 1848. Later that year he founded in Cartagena, Colombia, the newspaper 'La Democracia' with the intention of favoring the presidential election of general Obando - as successor of Jose Hilario Lopez. That same year he was named secretary of the government of Cartagena, and thus beginning his political life.
In 1853 he was elected to Congress. And later was elected governor of the Departamento of Bolivar. Between 1855-1857, during the government of Manuel Maria Mallarino, he carried out the ministries of property, and war.
In 1855 he published his first volume of political essays, under the name of 'La Federacion'. Later, under the government of Mosquera, he served as minister of national property.
After representing Colombia in the Ríonegro treaty, he travelled abroad. He first lived in New York city for two years, later he represented Colombia in Le Havre, and finally he became a Consul in Liverpool.
In 1874, while in Europe, many of the most important writings of Núñez were published.
He returned to Colombia in 1876 at the center of a political fight. He had been already selected, in 1875, as a candidate for the presidency, but did not manage to get elected. Five years later he occupied for the first time the presidency (1880-1882). Soon, in 1884, he was chosen president again, with the support of the Conservative Party.
The Constitutional reform of 1886, carried out with the collaboration of Miguel Antonio Caro, is possibly the most outstanding political performance of Núñez. This constitution, with some modifications, has been in effect since 1963.
From 1878 to 1888 he wrote hundreds of influential articles related to the constitutional reform for the newspapers 'La Luz' and 'La Nacion' of Bogota, and 'El Porvenir' and 'El Impulso' of Cartagena. He also wrote the lyrics for the Colombian national anthem.
He was once again re-elected in 1886 for the presidency and finally retired from political life in 1888, settling down in Cartagena, where he died in 1904.