In the scholarship on legal personhood, corporations have received significant attention. Beginning with oceans and maritime worlds, I offer a related, though often overlooked, history of legal personhood through the movements of the British merchant ship. As imperial technologies and juridical forms, these vessels facilitated imperial expansion, colonial dispossession, and racial enslavement. Through the projection and realization of imperial ambitions, however incomplete, merchant ships generated a vast accumulation of wealth while expanding claims of white British supremacy across oceans, territories, and the earth. As legal persons, merchant ships set the foundations for a maritime legal and financial infrastructure that was vital to the development of racial capitalism at sea and the rise of the modern corporation.