Born Pieter Cornelis Mondriaan, the artist was the second child of Pieter Cornelis Mondriaan, Sr., who was an amateur draftsman and headmaster of a Calvinist primary school. Piet Mondrian’s uncle, Frits, belonged to the Hague school of landscape painters. Both men gave Piet Mondrian guidance and instruction when, at age 14, he began to study drawing.