Leo XI was one well-connected guy. He was part of the Medici family, and his uncle was Leo X. It served him well - he made it to the papacy after all - but not for the long run. He died just 26 days into his reign (from April 1 to 27, 1605). The Italians called him Papa Lampo - Lightning Pope.*

*If there's a Posthumous Papal Superhero team, I think we all know what Papa Lampo's skill will be.