This paper presents previously unpublished material from the archives of the DAI and BSA, assessing its contribution to a better understanding of the settlement pattern on the north-east Aegean island of Lesbos in the Early Bronze Age, a period known only in terms of the single excavated sites of Thermi on its east coast. Using this new material evidence, the study places Thermi in its wider context within EBA Lesbos, demonstrating that several other EBA sites co-existed with Thermi, not only on the coast but also inland. It then places EBA settlements on the island in their west Anatolian context through an examination of ceramic parallels and affinities with mainland sites. It is argued: (1) that in view of the extensive distribution of EBA sites on Lesbos, colonization of the island must have begun long before the emergence of Thermi; (2) that several sources and mechanisms of colonization were involved in the process of settlement, which may be reflected in the fact that at least two distinct groups of sites can be identified on the island; and (3) that some of these sites appear to have relied upon agriculture rather than marine resources. Such inland agricultural sites may represent the first generation of purely endogenous communities which emerged on the island after its colonization.