Rasputin, the self-proclaimed magician and cult leader, wormed his way into the palace of the Romanovs, Russia's ruling family, around the turn of the last century. After getting a little too big for his britches, a few of the Romanovs allegedly decided to have him killed. But he was exceptionally resilient.
Reportedly it took poison, falling down a staircase, and repeated gunshots before Rasputin was finally dead. It's said that Rasputin mumbled a curse from his deathbed, assuring Russia's ruling monarchs that they would all be dead within a year. That did come to pass, as the Romanov family was brutally murdered in a mass execution less than a year later.
I thought I also heard that an additional part of the curse was that Russia would never be ruled again by the Romanovs. That has also come to pass.