William Warren (20 January 1839, Cambridge – 18th October 1914, Hemel Hempstead) was an English entomologist who specialised in Lepidoptera. William Warren was first educated at Oakham School, and subsequently graduated from the University of Cambridge, taking first-class classical honours in 1861. He then taught at Sedbergh School, Doncaster Grammar School (1866-1877) and Stubbington House School. He collected extensively in the British Isles, notably at Wicken Fen, with a special interest in Micro-lepidoptera. After giving up teaching in 1882, he lived in Cambridge and devoted himself fully to entomology, publishing around 40 papers on British moths between 1878 and 1889. Notably, in 1887 he was the first to recognise Grapholita pallifrontana (Lienig & Zeller) (Lep: Tortricidae) as a Bri