Very little is known about Guiljelmus Nicolai (Willem Claeszoon); he appears to have been a publisher and engraver, with Tooley's Dictionary of Mapmakers stating: 'thought to have worked in Lyons and Avignon, also possibly Leiden.' The confusion about Lyon and Leiden comes from these gores, because the imprint states 'Lugduni', which refers to modern-day Lyon in France, as well as Leiden, as chosen by Shirley. This might be because he is described as 'Gulielmus Nicolai Belga' in the imprint, referring to the Netherlands; and secondly, the only other set of these gores is in the University of Leiden.
Nicolai's cartography is not derived from the early 17th-century globes produced by the Hondius and Blaeu workshops but is based on sources from half a century earlier, and is most similar to the 1542 globe of Caspar Vopell.
Second copy known
Nova et integra universi Orbis descriptio.