He had moved in 2002 to Punta del Este, Uruguay's main tourist center, and last June he broke a hip for the second time in several months, a circumstance that resulted in a marked deterioration in his health.
An essayist, story-teller, historian, Diaz-Plaja was the author of more than 150 books, among which "El espanol y los siete pecados capitales" (1966) stands out with almost a million copies sold.
Born in Barcelona in 1918, he graduated with a doctorate in history from Madrid's Universidad Complutense and was a professor of history and Spanish culture at different universities around the world.
Among his best-known essays are "Historia universal de la cultura" (1946), "La vida espanola en el siglo XIX" (1952) and "El amor en las letras espanolas" (1963).
In 1989 he wrote "Cuando perdi la guerra", which was a finalist for Spain's Premio Espejo.