This paper explores the changes in indigenous masculinity and aggression during early foreign contact by whalers, traders, beachcombers, and missionaries who used Pohnpei as a major port of call; over four successive colonial regimes in Micronesia that had headquarters in Pohnpei; during Japanese militarization of the island in World War II; and in the American rule that followed. In the traditional culture of Pohnpei, various types of aggression served as key elements in assessing a man's manaman, a highly valued element in awarding a man a high title and the good life it afforded. A man's potential for aggressive behavior was hidden from public view, controlled, and limited in expression. Nevertheless, when aggression was called for, the cultural ideal was to express it in a dramatic, barracuda-like manner. These aggressive actions were most commonly enacted for the common good, especially for the benefit of the chiefs and the wider chiefdom. The indigenous Pohnpeian cultural notions of masculinity and aggression with modifications over these centuries of foreign contact are ones that Pohnpeians carry with them in diaspora, primarily to the United States, especially in the more developed Pacific Islands located nearby, such as Guam and Hawaii. This paper is based on the author's years of research as an anthropologist specializing in Micronesian cultures, particularly Pohnpei. Figures and references