Willem Janszoon Blaeu was a Dutch cartographer and publisher who lived during the Dutch Golden Age. He was born in 1571, possibly in Alkmaar or Uitgeest, Netherlands. Blaeu's early career involved learning the herring trade from his family, but he later became interested in mathematics and met Adriaan Anthonisz, a surveyor and astronomer who would become his scientific adviser. Blaeu moved to Amsterdam at the age of 23 to learn more about the herring trade, but instead focused on mathematics and cartography. He lived for two years on the Island of Hven, where he worked with Tycho Brahe, a celebrated Danish astronomer. Blaeu's work as a cartographer included creating maps and globes, and he was known for his innovative and accurate representations of the world. He published several atlases and maps throughout his career, including a world map in 1604 that was inspired by Gerardus Mercator's earlier work. Blaeu's rivalry with Jodocus Hondius and his heirs stimulated the production of globes, atlases, and maps to unprecedented levels during the Dutch Golden Age.