St. Dennis had a population of 2,696 in the 2001 census. According to the census one-quarter of the male population was employed in the extraction of china clay. The fraction of the population employed in the industry may have reduced since that date.
St. Dennis was part of the St. Austell Rural District from 1894 until 1974.
For more information, see the EN Wikipedia article St Dennis, Cornwall.
One of the many maps available on A Vision of Britain through Time is one from the Ordnance Survey Series of 1900 illustrating the parish boundaries of Cornwall at the turn of the 20th century. This map blows up to show all the parishes and many of the small villages and hamlets.
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