A group of performers, the Castellers de Barcelona, construct a nine-level human tower in Tarragona, Spain, in 2014. Photo: Roberta Esteves FernandezSpain is facing the greatest challenge in the post-Franco era to the nation's constitutional unity, as the Catalonian government in October 2015 issued a motion to unilaterally declare Catalonia's independence. The independence movement helped build support by using a 200-year-old cultural performance, the building of human towers (castells). The movement discarded other cultural performances (soccer, the sardana dance, and fire festivals), drawing from the human towers’ performative iconicity, associational culture, affective dimensions, and operative values to rally disparate social groups behind independence. In using human towers, the movement envisioned a solution to the ideological divisions of nationalist politics, but the instrumentalization of culture has a contradictory effect on politics. As European secessionist movements intensify, cultural performances reveal the objectives and risks of nationalist constructions.