Dr. Ramón Grau San Martín (September 13, 1881, La Palma, Pinar del Río Province, Spanish Cuba – July 28, 1969, Havana, Cuba) was a Cuban physician and the President of Cuba (1933–1934, 1944–1948). He was the last president other than an interim president, Carlos Manuel Piedra, to be born during Spanish rule. He is sometimes called Raymond Grau San Martin in English.
Grau's father, a rich tobacco grower, wanted Ramón to continue in his footsteps, but Ramón himself wanted to be a doctor. He studied at the University of Havana and graduated in 1908 with a Doctor of Medicine degree, then expatriated to Europe in order to expand his medical knowledge. He returned to Cuba in 1921 and became a professor of physiology at the University of Havana.
In the 1920s he was involved with the student protests against then–President Gerardo Machado, and was jailed in 1931. Upon his release he was exiled from Cuba, temporarily migrating to the United States.
After the 1933 Cuban Revolution Grau initially became one of the five members of the Pentarchy of 1933 government (September 5, 1933-September 10, 1933). Thereafter, on September 9, 1933, members of the Directorio Estudiantil Universitario met in the Hall of Mirrors in the Palacio de los Capitanes Generales and after intensive debate between various proposed candidates, it was agreed that Ramon Grau would be the next president. Ramon Grau was then President of what was famously called the government of One Hundred Days.