Manuel O. Campoamor was a pianist and composer of the early days of tango. In his youth, he performed in private parties and houses as well as in casas de baile were tango was becoming popular at the end of the 19th century. He was one of the first artists to record in Argentina both as a soloist and as accompaniment of other pioneers including Linda Thelma, Gabino Ezeiza, Higinio Cazón and Ángel Villoldo.
Manuel Oscar Campoamor was born in Montevideo in 1877. He was only 7 years old when his family moved to Buenos Aires. There he learned to play piano on his own while working as a telegraphist. In 1897 he was hired at the luxurious department store of Gath y Chaves where he remained for 25 years, working his way from the accounting department to a management position.
While Campoamor relied on these jobs all his life for to make a living, he also began performing in public as a pianist. He made his debut at la Casa Suisa when he was 17 years old  and quickly made a name for himself, performing in private parties and houses where tango was not yet admitted. Then he began performing in casas de baile such as la Casa de Maria la Vasca and Lo de Hansen. He composed his first tango “Sargento Cabral” in 1899, followed by “El séptimo cielo” (1900), “La c…ara de la l…una” (1901), “La metralla” (1902), “La franela” (1903) and “Mi capitan” (1905).
The tangos of Campoamor are the fast paced, lighthearted and often naughty tanguitos of the 1890’s. These are among the very first compositions which can be fully distinguished from other musical genres that came into the creation of argentine tango such as the tango andaluz and the milonga.
By the time tango was beginning to gain popularity in Buenos Aires around 1910, Campoamor already felt that his music was going out of fashion and significantly reduced his musical activity. He returned to tango in the early 1920’s, forming a cuarteto with Raimundo Petillo. The cuarteto turned into a sexteto and together they went on performing tango in their own old fashion manner as other musicians were already moving into the guardia nueva.
Manuel O. Campoamor died in died in 1941, never adhering to any of the various currents of renovation tango had been through during his lifetime. He did no express any resentment about the musical evolution of tango and simply said he did not identify with it. He is remembered as one of the great pioneers and proponent of the guardia vieja.
 Selles, Roberto. El tango y sus dos primeras décadas (1880-1900). La historia del tango. Corregidor, 1977. Print.
 Tango: Cien anos de historia (Vol. III). Buenos Aires: Editorial Perfil, 1992. Print.
 Silbido, Juan. Manuel Campoamor. Todotango. Online. http://www.todotango.com/creadores/biografia/507/Manuel-Campoamor/