Roberto Eduardo Viola was an Argentine military officer who served as the 48th President of Argentina and the 2nd President of the National Reorganization Process from 29 March to 11 December 1981 as a military dictator.

The National Reorganization Process was the military dictatorship that ruled Argentina from 1976 to 1983, which received support from the United States until 1982. In Argentina it is often known simply as the última junta militar, última dictadura militar or última dictadura cívico-militar, because there have been several in the country's history and no others since it ended.