In Spain, the popular challenge to austerity that began with the indignados movement — commonly abbreviated as 15-M, for May 15, the day the protests began in 2011 — has contributed to the rise of new political formations with broad support. Podemos, a party that emerged from 15-M, is now a major player in national politics.

In December 2015, the Spanish general election failed to produce a majority for the first time since the end of Franco’s dictatorship in 1977 — Podemos won about 20 percent of the vote, coming in just behind the center-right Popular Party (PP) and the center-left Socialist Workers’ Party (PSOE). Because Podemos refused to align with PSOE, no coalition could be formed, triggering a second round of voting.

Before the second set of ballots was cast in June 2016, Podemos entered into an alliance with United Left, a smaller party with roots in the historic parties of the Spanish left.