King Philip IV of France, deeply in debt to the Templars, had Jacques de Molay (Grand Master of the Knights Templar) and many other French Templars arrested in 1307 and tortured into making false confessions. When Molay later retracted his confession, Philip had him burned upon a scaffold on an island in the River Seine in front of Notre-Dame de Paris on March 1314.
While being burnt, Jacques de Molay cursed the French king and his entire Kapetings dynasty. No one knows whether it was a matter of his curse or just a historical coincidence, but all three sons of Philip IV died without surviving sons, causing the dynastical change in France.