Augustine Prevost, Jr. was the son of Augustine Prevost (1723-1786), one of four brothers who served as officers in the Royal American Regiment (60th Regiment), and dominated the command of that regiment from the 1750s until the end of the American Revolution. The Prevosts came, originally, from Poitou, France, but by the later 16th century this French Huguenot family was established in Geneva, Switzerland. The Royal Americans included men from several European nations, including Switzerland, and in addition to the Prevosts, two officers of Swiss origin who also gained prominence were Henry Bouquet and Frederick Haldimand. The younger Augustine Prevost was born in Switzerland, but was sent to military school in England at an early age. He was commissioned an ensign in the Royal Americans at the age of fourteen in 1761. Soon afterward he joined his father, who was by then a lieutenant-colonel, in Pennsylvania. On 15 April 1765, Augustine Prevost Jr. married Susannah Croghan (1750-1790) in Lancaster, Pennsylvania. She was the daughter of George Croghan, Sir William Johnson's highly respected deputy Indian agent for the western Indians. Unfortunately, George Crogan was heavily involved in land speculation, and this proved to be financially disastrous for him and for his son-in-law, Augustine Prevost, who had been persuaded to join him in his financial ventures.
Augustine Prevost, Sr. attained the rank of major-general during the American Revolution, and Augustine Prevost Jr. served under his father's command during the war. He became deputy inspector-general of Provincial Forces while in Charlestown, South Carolina, and was present at the siege of Savannah, Georgia. When Charlestown was evacuated in 1782, he sailed with his regiment to New York, but remained in America when the Regiment returned to Britain. Augustine Prevost, Jr. was a close friend of Joseph Brant from his early years in America and through his connection with
George Croghan, whose Indian daughter Catharine had married Joseph Brant. Of his many children, lieutenant James Prevost and lieutenant Henry Prevost were both killed in 1811 fighting under Wellington in Portugal, and John Augustine, who became a lieutenant-colonel, was lost at sea. While Augustine Prevost Jr. attained the rank of major during the American Revolution, he did not reach the rank and distinction of his brother, Sir George Prevost, who rose to become a lieutenant-general in the British army and Governor General of Canada. Augustine's son George Augustine retired as a British army major and the administration of the Croghan estates and financial affairs fell to him. Augustine Prevost died on 17 January 1821 at his home in Greenville, New York.
In August of 1777, Augustine Prevost, Sr. sent his son, Major Augustine Prevost, to Pennsylvania to recruit for the 1st Battalion of the Royal Americans and to assist George Croghan in resolving a dispute with the Shawnee Indians. The trip also provided an opportunity for Augustine to meet with Croghan concerning their tangled financial affairs. The Diary, kept by Augustine on that journey from Lancaster to Pittsburg, is a record of the events that occurred during the trip. The first few pages at the beginning of the Diary are dated April 1774. They describe the departure of the Prevost family from Kingston, Jamaica, where the battalion had been stationed for two years, and their journey to Philadelphia. On 4 August 1774, Augustine Prevost left his home near Lancaster, Pennsylvania, and began the long journey to carry out his orders to recruit men for the Regiment, and to meet with Croghan concerning both Indian affairs and their financial situaltion. The Diary ends when he left Pittsburg in September of 1774 with the twenty-one men he had recruited. In November, he sailed with his regiment for Jamaica.
Accompanying the Diary, and as part of the introductory material written by Nicholas Wainwright and filmed at the beginning of the reel, is a section entitled, "Notes". The information it contains is most useful in providing background information on people, places, and events relating to the Diary. The "Notes" are arranged by the date in the Diary to which they refer. At the end of the Diary, several personal accounts with individuals have been recorded, and from 25 August until 3 September there is a record of the cost of food and lodging.