Was a Flemish engraver, globe maker, and publisher who spent most of his career working in England and the Holland. His Latinised name was Petrus Kaerius. He was born in Ghent in 1571 to engraver Hendrik van den Keere and moved to London with his family around 1583-4 for religious reasons. In London, he received training as an engraver from his brother-in-law, Jodocus Hondius. In 1593, they both settled in Amsterdam.
There is little information known of his life.