This paper examines the process which dispersed the moveable heritage of the Monastery of São Dinis de Odivelas, founded by King Dinis at the end of the 13th century, through an analysis of the inventories compiled from 1886 in the wake of the nationalisation of the dissolved convent. The inventories, stored in the Arquivo Nacional da Torre do Tombo, Lisbon, and never previously studied, demonstrate the importance of inventorying movable and immovable assets from the point of view of their conservation, thus providing a basis for further research on the subject. The first part of the paper describes the monastic complex when it came into the possession of the State, as presented in the unpublished Memórias descritivas of 1887 and 1889, also kept in the national archive. These reports reveal the state of abandonment and decay of the monastery, which had already been stripped of its rich and valuable possessions. The concluding section then deals with the vicissitudes of a precious chapiter, a rare architectural piece dating from the foundation of the convent, disputed between different institutions, which has now disappeared, presented here as an emblematic case-study of the fate of most of the Odivelas monastic heritage.