The Prologue is the first chapter of The Peoples of Middle-earth. It is the shortest chapter in the book because the history of the Prologue is fairly straightforward: the original text remained largely intact and was mostly just expanded until published in The Lord of the Rings. In discussing the history of its writing Christopher Tolkien identified seven versions of the text, which he labeled P1 through P7.
P1 was begun in the years 1938 to 1939. Much of it remained as it was when published. What P1 lacked was the history of the Hobbits in section one, all of section two "Concerning Pipe-weed", and all of section three "Of the Ordering of the Shire". Also, what would later expand into section four was just a brief mention of the story of Bilbo and Gollum when they met, and the "Note on the Shire Records" was still in the future.:3
P2, a typescript of P1, had only minor changes except for a much expanded recounting of Bilbo and Gollum’s interaction, which still followed the storyline of the 1937 edition of The Hobbit – if Gollum had lost the Riddle Game he would have given his ring to Bilbo. J.R.R. Tolkien set P2 aside for some years and when he returned to it he added information that would become section 3 "Of the Ordering of the Shire" and section 2 (which was headed "Tobacco"). Since P2 carried the original story of Bilbo and Gollum, Christopher stated that this version could not have been written after July 1950 and he believed it was written in 1948.:3-7
The next two stages, P3 and P4, are mentioned only briefly. P3 was a new typescript of P2 with many minor corrections. P4 was simply a clean typescript of P3.:7
P5 contained a great deal of new material. Tolkien discussed the martial qualities of the Hobbits although the Battle of Greenfields did not yet appear (however the word mathom did). Christopher believed that when "The Scouring of the Shire" was written and Greenfields was mentioned it was then added to the Prologue material.:7-11
P6 brought the Prologue near to the form it had in the first edition of The Lord of the Rings. It was still missing the division into four numbered sections and the finding of the ring still followed the original Hobbit. The Battle of Greenfields was now included.:11-12
P7 was essentially the version of the Prologue as published in the first edition. It finally contained the "true tale" of the finding of the Ring. However, the Prologue did receive addition information in the second edition, the "Note on the Shire Records". Tolkien originally planned to have this information in the preface to The Silmarillion.:12-15