John Buffett arrived on Pitcairn Island in the whaler Cyrus in 1823. He married Dorothy Young, daughter of Midshipman Edward Young, a mutineer of HMS Bounty. In 1856 Buffet moved to Norfolk Island with 193 other Pitcairners in the ship Morayshire.

The diary begins on 8 June 1856, the day of arrival at Norfolk Island. It is kept in a year book of Norfolk Island's convict era, which Buffett apparently found in one of the abandoned buildings at Kingston. It continues to 16 (?) September 1860. There is then a gap until 28 March 1868, when Buffett returned to Pitcairn, where he remained until 4 July 1872. There is then another gap until 17 October 1872 when Buffett returned to Norfolk Island, keeping the diary until 2 October 1875. Another break then occurs until 26 May 1879, when the diary appears to have been continued in another hand until 31 August 1879. From 1 January 1888, when it again resumes, various hands appear. After a break between 4 August 1888 and 1 January 1889, it continued uninterrupted until 31 March 1892. The death of John Buffett, Sen., is recorded on 5 March 1891. The diary is the day by day affairs of the island on which Buffett happened to be - shipping arrivals and departures, births, marriages and deaths, the state of the weather, chases after whales and other remarkable events. At the front and back of the diary are a number of miscellaneous items, including the text of hymns, a description of a dream, the laws and regulations of Pitcairn Island, recipes, poems and copies of letters and Commissariat details.