The Pilgrim's Progress: A Dream that Endures
http://www.ctlibrary.com/ch/1986/issue11/1124.html
This essay by James Forrest explores the legacy of The Pilgrim's Progress. Particularly, he traces some of the reason's for the book's enduring popularity and its resonance with modern readers.
Meet Puritan John Bunyan
http://puritanrising.com/2011/09/meet-puritan-john-bunyan-1628-1688/
This site provides a good, concise biography of John Bunyan.
The Online Books Page: Online Books by John Bunyan
http://onlinebooks.library.upenn.edu/webbin/book/lookupname?key=Bunyan%2C%20John%2C%201628-1688
A link to online versions of much of John Bunyan's corpus.
England and English History: Restoration England
http://www.englandandenglishhistory.com/english-social-history/-restoration-england-1660-ad
This site provides a timeline of important events of the turbulent Restoration period.
The Norton Anthology of English Literature: The Early Seventeenth Century: Topics)
http://www.wwnorton.com/college/english/nael/17century/topic_3/welcome.htm
This site provides an excellent and scholarly introduction to the literature of the seventeenth century. All of the links on the left side of the page on the seventeenth century are relevant and should be explored.
The Cambridge History of English and American Literature: Cavalier and Puritan
Scroll down to Part VII, which is all about John Bunyan. Good, scholarly articles on Bunyan's life, major works, and influence.
The English Puritans
http://www.monergism.com/thethreshold/sdg/brown/brown_englishpuritan.html
This extensive overview of English Puritans will be useful to those who wish to better understand this diverse group of Christians.
Map of Pilgrim's Progress
http://en.wikipedia.org/wiki/File:Pilgrim's_Progress_map_small.JPG
This engraving from a 1778 edition of The Pilgrim's Progress provides an interesting visualization Christian's journey to the Celestial City.