This paper discusses two objects once owned by the antiquary Thomas Lyte (1568–1638). The Lyte Genealogy, now in the British Library, is an illustrated pedigree of Britain’s monarchs, tracing the royal succession through multiple lines of descent from the Trojan prince Brute. It demonstrates the importance of antiquarianism, and the continuing relevance of the traditional British history derived from Geoffrey of Monmouth, in supporting the legitimacy of the Stuart succession. The Lyte Jewel, now in the British Museum, is a tablet miniature containing a portrait of James i by Nicholas Hilliard, presented to Thomas Lyte by the king as a reward for his work on the Genealogy. New evidence points to the king’s jeweller, George Heriot, as its likely designer. Together, the Lyte Genealogy and the Lyte Jewel offer new insights into the antiquarian pursuits of the early Stuart gentry and the intellectual and material culture of the Jacobean court.