Johan Sems

Johan Sems (1572 – January 1635), sometimes known as Johan Semp, was a Dutch cartographer, engineer and land surveyor. He specialized in land reclamation and the building of dikes and fortifications.

Sems was born in Franeker (Friesland) in 1572 to Sem IJsbrandts and Claesgen Adriaens. Sems is a patronym. Sem IJsbrandts registered himself as a student at Leiden University. The family lived on the Marendorp Landzijde on the corner of the Lange Hooglandse Kerksteeg in Leiden. IJsbrandts committed suicide in 1584 due to alcoholism. Johan Sems did not go to university himself. He had probably learned his skills in practice.

Little is known about his children.

Sems was married twice: first to Baerthe van Soutelande and then to Catharina Jans.

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