I think it would be difficult to argue that anyone other than Geoffrey Chaucer is the father of English literature. As mwestwood points out, Chaucer wrote in the English vernacular and used iambic pentameter. He also wrote darn good stories! Humorous, satirical, and memorable, Chaucer’s Tales have stood the test of time. No American teacher of high school senior English would think of starting off the school year without visiting Canterbury. Every student who graduates from an American high school might not remember a lot about English, but he certainly remembers the running sore on the Cook’s leg.
Chaucer, certainly. In addition to the contributions already mentioned, Chaucer created a rich portrait of English society during his time. Through the choice of pilgrims he included on the journey, he captured almost every aspect of society, except for royalty. Also, his social criticism of the corruption in the Church was quite pointed and memorable.
I agree with the previous post. The ideas of Chaucer's development of characterizations and a large depiction of the motivations of characters in his work become critical elements in English literature after Chaucer. The notion of creating multi dimensional characters are powerful elements in the landmarks of post Chaucer English Literature.
Because he wrote "The Canterbury Tales" in the vernacular of the English people, Geoffrey Chaucer is often credited with being the "Father of English literature." During Chaucer's lifetime, most literary works were written in French; in fact, Chaucer himself wrote in French and Italian; certainly his poetry was modeled upon French poetry. However, he chose to write in the Old English that was popular with those who were not necessarily among the nobility. In addition, his stories have a humor and freedom that anticipated the works of such English greats as Henry Fielding.
Also, he did introduce iambic pentameter into poetry, a meter that many a reader recognizes as that of William Shakespeare and is prevalent in much of English and American poetry.
I would definety say Chaucer.