This is not intended to be an exhaustive list of such tales but it demonstrates that just in the North East of England alone there is a rich hoard of serpent lore and this reflects England as a whole and other parts of the Germanic and Aryan world. According to Joyce Tally Lionarons in The Medieval Dragon. The Nature of the Beast in Germanic Literature (1998) there is even a Proto-Indo-European verb, *ghen to denote the action of slaying a dragon so we may infer from this that the entire concept goes back to Indo-European prehistory. The correct native English term is worm or wyrm from the Old English wyrm. Dragon however is ultimately a Latin word from which the Old English draca is derived. The Old Norse ormr is very similar to wyrm. These terms can be used for either 'serpent/snake' or 'dragon'.
Of course ultimately these dragon or serpent slaying heroes may be traced back to *Thunaraz in the Germanic world and His Indo-Aryan cognate Indra.
"I WILL declare the manly deeds of Indra, the first that he achieved, the Thunder-wielder. He slew the Dragon, then disclosed the waters, and cleft the channels of the mountain torrents.
"He slew the Dragon lying on the mountain: his heavenly bolt of thunder TvaStar fashioned." (Rig Veda, Hymn XXXII 1,2, Ralph T.H. Griffith translation)
If the Eddas of course we have a number of encounters between Thor and the Midgardsorm, the world serpent who will be the bane of Thor at Ragnarok but who in turn will be slain by Him.
What does all this serpent slaying indicate? Of course we have the traditional interpretation of this as a nature myth of the eternal struggle between light and darkness, day and night and on a certain level this is correct but there is another interpretation which was proposed by the emminent scholar Professor Laurence Austine Waddell. Aryan man thousands of years ago was involved in the eradication of an evil serpent cult which was lunar in type and involved wholscale human sacrifice. Many of the stories contained within the Aryan mythologies describe battles between an incoming and dominant Nordic people who sought to wipe out this cult which it is important to understand was matriarchal, matrilineal, lunar and cthonic. Eventually the patriarchal solar religion of Nordic Aryan man dominated those civilisations which he planted. In The Rise of Man in the Gardens of Sumeria. A Biography of L.A. Wadell (2009) Christine Preston restates the 19th century hypothesis that "human society in the period of 7,000 to 2,000 BC was matriachal, and that a mother-cult with the 'figure of a goddess and dying god' was widespread". She refers to the work of the Lithuanian scholar Marija Gimbutas who speculated that human societies from the Near East to Western Europe were originally matrilineal (The Gods and Goddesses of Europe, 1974 and The Living Goddesses, 1999.) Traces of this matrilineal society may be found amongst the non-Indo-European Basques, Iberians and Picts.