I wonder who his heir or successor might be today....
Both the orthodox Christians and the non-Roman-Catholics were divided into two camps: as to who was going to go along with the Nazi plan (see Confessing Church (during Nazi Germany) or Confession Movementand Barmen Declaration). Relevantly, Pius XI died shortly after coming out against the Nazi regime.
P.S. If you look at the USA and UK today, the same kind of division is being attempted. Except they might skip that and just go wit the Ishmael vs Isaac--I mean Islam vs. Israelites/orthodox Christians.Pius XI planned an encyclical Humani generis unitas (The Unity of the Human Race) to denounce racism in the US, Europe and elsewhere, as well as antisemitism, colonialism and violent German nationalism. He died without issuing it. (source)