Why is the Norman Conquest of 1066 so important to us as we read English literature?
The Norman Conquest of 1066 is important in studying English literature in that it was the time when Britain's language and culture moved from Anglo Saxon to Norman French. The French language at that time was the language of literature. The French culture valued literature (it was from them that the bulk of the Arthurian legend came to be written down) and promoted it throughout the lands where its culture was an influence, including Britain.
The English language was extraordinarily enriched by the infusion of Norman French. It expanded the range of the language, giving it more descriptive words that showed a depth of meaning beyond what Anglo-Saxon was able to do. Much of the English vocabulary today is based on French.
Very little literature from Angl-Saxon Britain survives in written form. However, after 1066, English literature began to grow and thrive.
Because of the Norman Conquest, the written language, that of the Norman nobles who virtually slaughtered most of the Saxons at the Battle of Hastings, became French. This Old French was the language of the Arthurian legends (e.g. "La Morte d'Arthur". But, when Geoffrey Chaucer wrote "The Canterbury Tales" he broke with tradition and wrote in Old English.
Nevertheless, the sentence structure of Old English is much like French (e.g. of + noun for possessives, adjectives follow nouns )and meanings of many of the words are the French meanings. If a student has had French, he/she can more easily read this Old English literature. In fact even in modern English, more than 60% of the words are derived from French. So, this French influence continues today as French is a parent language of English.