I thought it might be helpful for us to have a place where we can collect all the evidence we have for how many Earl's of Grantham there have been - even if some of that evidence is contradictory.
This is for evidence from canon sources, either the show itself, the behind the scenes books, or other official sources (see our policy on canon if you're unsure what canon is).
This is for evidence which we're unsure of. Either because it may or may not be canon, or for some other reason.
If anyone has anything I've missed, or anything else we should consider then please leave a comment!