Okay, let's throw down an interesting challenge here. With a PoD from 1850 (the annexation of Hohenzollern-Sigmaringen and Hohenzollern-Hechingen to Prussia) onwards, have a member of the Catholic Swabian branch of the Hohenzollern House (Sigmaringen or Hechngen) become Emperor of Mexico. Bonus points if said Empire lasts to the 1950's.