Gerolamo Gerini graduated from the Modena military academy in 1878, and upon discovering that the Royal Army of Siam was looking for European officers to train their soldiers, he decided to enlist. He joined the army of Siam as a lieutenant in charge of training cadets. A prolific writers, Gerini wrote several volumes on the culture, customs, history, archaeology, language, and religion of Siam and was a regular contributor to the Asiatic Quarterly Review. His essay on the archaeology of Siam appeared in The Kingdom of Siam 1904, that A. Cecil Carter edited for the Louisiana Purchase Exposition. In 1911, Gerini collaborated with the Royal Siamese Commission for Foreign Exhibitions in the preparation of the exhibits for the Pavilion of Siam. The Executive Committee for the Siamese exhibit in Turin was composed of Gerini himself (Commissioner-General), A. Rigotti (Techinical Director for the building of the Pavilion), and G. Vigna del Ferro (Secretary).