Oh god, who cares? I don't find any British history interesting. I don't find early American history interesting (anything pre 1776 just puts me to sleep). I'm not arguing importance, I'm just saying that I don't give a shit.
This is now worse then the time some people on this forum freaked out when I hated Eaters of Light last season (partially because it was based on an obscure, stupid piece of history that was barely relevant to people in the UK, much less the world). At least King james is more relevant then whatever the fuck the Picts were, and will probably be an asset to the story being told. That is my barometer for historical stuff in Doctor Who. if it enhances the story or enables a good story, its good. If it holds back the story or brings it down, like in Eaters of Light, its bad. Actual historical importance dsoesn't factor into it. I love the Agatha christie episode in series 4, but you couldn't pay me to read one of her books.
Some people don't give a shit about British royalty or anything related to it. Probably a lot of people in the UK too, much less in the US. Just accept it, it doesn't hurt you or anything. It doesn't mean the DW episode will be bad. I don't give a crap about Queen Elizabeth (?) either, but I still really liked Day of the Doctor and the scenes with her were funny. I admittedly actually just had to google the episode because I thought she was Queen Victoria, but even stuff like that doesn't effect an episodes quality (seriously though, British royalty needs to know that there are more then 4-5 boy and girl names in existence). The actual history in Doctor Who is almost always second to the story. Except when it comes to those Picts, I'm still a bit irrationally bitter about that episode and its shitty obscure British history fucking up the story. But even then its only because the story was held back by the history.
In the end, history is only important in DW in setting up the backdrop or guest characters. Besides that, its the story thats important, not what historic figure The Doctor is meeting or what historical event The Doctor is seeing/participating in.