What's the name of historical child-noble, took part in failed war/conspiracy, died before could conceive heir?

A while back I stumbled upon the wikipedia page for a historical figure, a young boy who'd become either an obscure king or minor nobleman, and was somehow swept into a complex military campaign, battle, conspiracy, insurrection, or something along those lines. He died before he could reach adulthood, and in their desperation his handlers even threw his wife at his deathbed in doomed hopes of his conceiving an heir before imminent death. Anyone know who this was?