This chapter focuses on Henry Ellis, who has made occasional appearances in earlier chapters of this book. Like Arthur Dobbs, Ellis was one of those second-tier figures of eighteenth-century British imperial history who frequently influenced or exemplified important historical developments. In a sparkling 1970 essay, John Shy used Ellis to help illuminate the “spectrum of imperial possibilities” following the Seven Years' War. In this book, Ellis has spoken confidently of the great islands of necessity existing in the North Pacific. He has participated in the 1746–1747 British expedition in search of a Northwest Passage from Hudson Bay, and his account of the voyage, and the continuing openness to the existence of the passage it exhibited, seems to have been one of the key documents that alarmed late 1740s and early 1750s French officials with the scale of British ambitions.