The narrator is an unnamed crewman, presumably the captain, of a Spanish merchant ship in the early 17th century. Acting as a surrogate for the reader, he is curious and observant as he engages in philosophical dialogues with the leaders of Bensalem. His primary motivation is the survival of his crew, which quickly transitions into a desire to understand the isolated utopian society they have discovered.

The Father of Salomon’s House is an elite leader within Bensalem's national academic institution. He represents the pinnacle of the island's scientific and religious harmony, blending the trappings of a clergyman with the intellect of an empirical researcher. He is devoted to uncovering the secret motions of things and expanding human knowledge for practical, societal benefit.

Joabin is a Jewish merchant and one of the few named individuals the narrator meets on Bensalem. Described as wise and highly educated in political matters, he acts outside official state or church capacities. He serves as an expert on the island's laws and customs, praising the society's strict adherence to chastity and familial loyalty.

The Governor of the Strangers' House serves as both a political official and a Christian priest in Bensalem. He is the foreigners' first point of official contact, responsible for ensuring their needs are met while maintaining the island's strict isolationist policies. He possesses a deep knowledge of global history, including the ancient fate of the original Atlantis.