Verdejo has been the grape of Rueda since perhaps the eleventh century, an old Castilian variety possibly carried north during the Mozarab resettlements of the Duero frontier. For most of its history it made a wholly different wine from today's: oxidative, amber, sherry-like, matured in the underground cellars that honeycomb the meseta towns.
Its modern life began in the 1970s, when the Rioja house Marqués de Riscal, advised by the Bordeaux oenologist Émile Peynaud, came looking for a crisp Castilian white and found it dormant in Rueda's old vines. Cold fermentation revealed what the flor had hidden — fennel, bitter almond, laurel, a saline cut — and night harvesting now protects that edge from the meseta's daytime heat.