Well, Sallah has only ever appeared in Indiana Jones movies that have involved the Middle East.
That's the spirit! Part of the good thing about Kingdom is that it'll make Doom feel less like an oddity and more like a unique adventure. So no Sallah or Brody in this installment, but we got Marion.
Raiders: Primarily Middle East setting with a Biblical artifact, Marion, Sallah, Brody, South American prologue, Nazis
Doom: Wholly Asian setting, Hindu artifact, Thugees, Chinese gangsters, mercenary Indy, Indy is an "adoptive" father
Crusade: European / Middle East setting with a Biblical artifact, Nazis, Sallah, Brody, Prologue spanning from Indy's childhood, deals with his own father
Kingdom: Older and wiser Indy, Marion, South American setting, Russians, likely prologue set in the US, "alien" artifact and potential flesh-and-blood son