The post-1945 years saw the erosion of some Welsh traditions, such as religious non-conformity and Sunday closing, but the increasing reassertion of Welsh distinctiveness [REF].
Over the course of the 20th century, the population of Wales increased from just over 2,012,000 in 1901 to 2.9 million in 2001, but the process was not linear - 430,000 people left Wales between 1921 and 1940 largely owing to the economic depression of the 1930s [REF].