Hi, Rusty!
Now......you ask why would the Bishop of Ely even have a palace in London in the first place?
Because, like many other bishops, the Bishop of Ely had a seat in the House of Lords, and his parliamentary duties meant that he would have to spend a part of the year in London.
Therefore it made sense to have a home there.
But considerable efforts were made to ensure that such residences weren't subject to the laws - and taxes - of London.
So an "enclave " was established and Ely Place was legally a part of the Diocese of Ely, Cambridgeshire, despite its London location!
So this former residence of the bishops of Ely, for a very long time, was not actually regarded as officially part of London!
It remained a little bit of Cambridgeshire - even enjoying freedom from entry by the Metropolitan police, unless invited by its own governing body, the Commissioners of Ely Place.
The address for instance of the local pub used to be ""Ye Olde Mitre Tavern, Ely Place, Holborn Circus, Cambridgeshire"!
How about that for an interesting titbit of information!
Now, time for Eggheads...!
Like General MacArthur, "I shall be back......."