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.
Canon evidence
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).
- The book The Chronicles of Downton Abbey: A New Era tells us that Robert is the 7th Earl of Grantham.
Possible evidence
This is for evidence which we're unsure of. Either because it may or may not be canon, or for some other reason.
- This paparazzi picture shows the grave stone of Sybil Branson, which describes her as "daughter of the 5th Earl". However, this can not be taken as canon information unless it comes from a canon source - e.g. it appears in the show.
If anyone has anything I've missed, or anything else we should consider then please leave a comment!