The 1911 census is a record of everyone who lived in England and Wales in 1911. The official UK 1911 census website, in association with The National Archives. Free index search with pay per view access to detailed information and images.
Comprehensive database of UK family records online. Search for free and pay to view the results. Birth, Marriage & Death records from 1837-2004; People Census 1861; Address Census 1861; Electoral Roll records from 2002-2007.
In the event of war a National Register was taken that listed the personal details of every civilian in England and Wales. The 1931 census was destroyed by fire. No census was taken in 1941 because of the war. So the 1939 register is the only national census-like resource available for this period. Findmypast has searchable indexes; database results and some digitized images are available with a fee-based subscription.