Digital Collections Related to 20th Century Britain:
This list is a work in progress - I welcome any suggestions!
Observing the 80s, https://blogs.sussex.ac.uk/observingthe80s/background/
Life Magazine from 1936-1972 https://books.google.com/books/about/LIFE.html?id=N0EEAAAAMBAJ
Sainsbury Archive, documents, images, advertisements and more from Britain’s main grocery store chain. Mostly 20th c https://sainsburyarchive.org.uk/