Willem Janszoon was the founder of the Blaeu cartographic dynasty, synonymous with the finest mapmaking from The Netherlands. He studied astronomy and instrument-making under Tycho Brahe before moving to Amsterdam. In addition to maps, Blaeu designed a completely original globe in 1599, and his subsequent productions were distinguished by their up-to-date astronomical information. Willem Janszoon's sons joined him in the firm, with the eldest Johannes (1596–1673) quickly assuming the lead. After Willem Janszoon died, Johannes expanded the ‘Atlas Novus’ into the ‘Atlas Maior’, the largest and grandest atlas of its time.