Eustache-Antoine Hua (1759-1836) was a barrister and a public prosecutor from Mantes who lived through a succession of historical eras, from the last decades of the monarchy to the French Revolution, the First French Empire and finally the Bourbon Restoration. He is mostly known for his memoirs : when he was a member of the Legislative Assembly, he undertook to report and analyze the historical events that unfolded during his term of office, and to describe his personal and professional life, from his time as a student of the law until the year 1827. His grandson Eustache-Maur François Saint-Maur (1825-1901) had the memoirs published in 1871. The first part of this thesis is a study of Hua's Mémoires, from the time of writing to the time of publication, while the second part extends the study to the other private documents found in the Hua collection (Archives nationales, 621 AP). These documents are an abundant source of information about their author and the era he lived in. This thesis thus includes the biographies of both Eustache-Antoine Hua and his grandson, as well as a complete critical edition of the Mémoires. It also analyzes an example of a publication led by a member of the author's family (raising issues of censorship and family history preservation), and studies of the various facets of the character that was Hua (as a citizen, a traveler, a father, etc.), which show in the Hua collection's egodocuments : memoirs, letters, travel diaries. Furthermore, those documents give a first-hand account of French society and culture in the early 19th century, particularly on the subjects of family and traveling, a topic reviewed in the last chapter of this thesis