Acquisition, duplicates and exchange: C. P. de Bosset's collections from Cephalonia, Ithaca and Delphi in the British Museum.

This article focuses on the acquisition, management, and provenance of the archaeological and numismatic collection assembled by Charles Philippe de Bosset (1773–1845), a Swiss soldier and British imperial official active in the Ionian Islands. It clarifies that the British Museum acquired de Bosset's collection of coins, bas-reliefs, and a bronze in two stages—primarily in 1815 and additionally in 1818—correcting previous assumptions that the entire collection was obtained in 1818. The study examines the museum's early nineteenth-century practices of acquiring large coin collections and subsequently removing duplicates through sales and exchanges, using de Bosset's collection as a case study. It also reconstructs the archaeological provenance and catalogues part of the collection related to Cephalonia, Ithaca, and Delphi by cross-referencing de Bosset's 1815 publication and museum records, thereby restoring provenance details lost for over two centuries. The article highlights the importance of archival research and contemporary publications in understanding nineteenth-century collection management and provenance restoration within public institutions.