David Dean O'Keefe (1824 or 1828[1] - 1901) was an Irishman who immigrated to Savannah, Georgia, USA before becoming a historical figure to the island of Yap.
He left the United States in 1871 for the South Pacific. After landing on Yap he became powerful by using tools from Hong Kong and East Asia to more easily create Rai stones. However the easier ability to make the stone money ultimately helped lead to its decline during the period of German rule.[2] Still the wealth allowed him to own an island, which he was considered "king of." Reportedly he had his own emblem, which showed the US flag waving over the letters "OK." He ultimately accepted a Yapese wife as well, despite already having a wife and daughter in Savannah.
In 1901 he died on the ship Santa Cruz, which was on a return to Savannah.
The book His Majesty O'Keefe by Lawrence Klingman and Gerald Green, Copyright Charles Scribener and Sonx, 1950 is a narrative of O'Keefe's life. A film was based on the book. The film His Majesty O'Keefe is a dramatization of his life.