Barbosa (birth name: José Celso Barbosa Alcala) was born in the city of Bayamón, Puerto Rico to parents of African and European ancestry. He received both his primary and secondary education in Puerto Rico. He was the first person of mixed-ethnic ancestry to attend Puerto Rico’s prestigious Jesuit Seminary. After graduating from the Seminary, Barbosa tutored private students to save money to attend college. In 1875, he moved to New York to attend prep school, where he learned English in a year.

Originally Barbosa wished to become a lawyer, but after he suffered a bout of pneumonia in New York City, his doctor recommended that he study medicine. In 1877, he was admitted to the medical school of the University of Michigan, where he graduated valedictorian of the class of 1880. Barbosa was the first person from Puerto Rico to earn a medical degree in the United States. He returned to Puerto Rico, where he set up his practice in his hometown of Bayamón.  At first the Spanish colonial government did not recognize Barbosa’s medical degree, as it was not from one of the European universities. The American consul to the island intervened on behalf of Barbosa to have his degree recognized, so he could practice.  Barbosa provided medical care all over the island. He introduced the novel idea of employers paying a fee for the future healthcare needs of their employees (a very early health insurance system). In 1893, Barbosa founded the first Puerto Rican cooperative and named it El Ahorro Colectivo.

During the colonial period, Barbosa was a member of the Autonomous Party led by Román Baldorioty de Castro, but left because of ideological differences.  In 1898, when the United States bombarded and blockaded San Juan during the Spanish–American War, Barbosa and other doctors who lived in Bayamon, traveled to the town of Cataño and took a ferry to the capital. Barbosa, as member of the Red Cross, went to the aid of the wounded Puerto Rican and Spanish soldiers. He and his party on the ferry had to travel across San Juan Bay at risk, as they were under cannon fire. Barbosa and those with him were recommended by the Spanish government for the Cruz de la Orden del Mérito Naval (The Cross of the Order of Naval Merit) for their bravery.  As a result of the war, the United States made Puerto Rico one of its territories. On July 4, 1899, Barbosa formed the pro-statehood Puerto Rican Republican Party. He became known as the father of the “Statehood for Puerto Rico” movement.

On June 5, 1900, President William McKinley named Barbosa, together with Rosendo Matienzo Cintrón, José de Diego, Manuel Camuñas and Andrés Crosas, as part of an Executive Cabinet under U.S.-appointed Governor Charles H. Allen, the first civilian governor of the island. The Executive Cabinet also included six American members. Barbosa served on the Executive Cabinet until 1917, dealing with a variety of governors appointed by the US during that period, and providing continuity in administration.  During this period, in 1907 he had established the newspaper El Tiempo, the first bilingual newspaper on the island.

With representative elections authorized in 1917, Barbosa ran for a seat at large. He was elected, serving as a member of the first Puerto Rican Senate, from 1917 to 1921.  José Celso Barbosa died in San Juan on September 21, 1921. He was laid to rest in Santa Maria Magdalena de Pazzis Cemetery in Old San Juan. His daughter Pilar Barbosa became a renowned historian, the Official Historian of Puerto Rico from 1993 to 1997. She was also a political activist who carried on her father’s work.