Many accurate 1921 census transcriptions have already been added to the pub history site, including London, and parts of Middlesex.
Westminster St James index
The Nags Head is actually in St George Martyr as was the top western section of Swallow street. All of Swallow street except the lowest section was demolished to make way for Regent street in about 1815.
Historical London public houses, Taverns, Inns, Beer Houses and Hotels.
Residents at this address
16 March 1790/Insured: John Hallock, The Nags Head, Swallow Street, victualler and coachmaster/../Records held at the LMA
1805/_ Pix, Nags Head, 96 Swallow street, Oxford street/../../Holdens Directory
1806/Mrs Pix, Nags Head, Swallow street/../../London Brewery 1806 customer for supplying the public with genuine malt liquor
1811/James Hill, the Ship, Swallow street/../../Holdens Directory