Which club won five straight La Liga titles from 1985-86 through 1989-90?

Real Madrid won five straight La Liga titles from 1985–86 through 1989–90.

The run began in 1985–86, when Real Madrid ended a six-year wait for the league championship. The team won that season by an 11-point margin and also captured the UEFA Cup, creating a memorable European double. It then retained the Spanish title in each of the next four seasons.

The five championships were won during the era associated with La Quinta del Buitre, a celebrated generation of Real Madrid players led by Emilio Butragueño. Other prominent figures included Manuel Sanchís, Martín Vázquez, Míchel and Miguel Pardeza. Dutch manager Leo Beenhakker guided the club for much of the sequence.

Real Madrid completed the streak in 1989–90, when it won its fifth consecutive title and equalled its own earlier record from 1960–61 through 1964–65. Barcelona, Atlético Madrid and Valencia have all been major Spanish clubs, but none won this particular five-season run.