Pieter de la Court (1618 – May 28, 1685) was a Dutch economist and businessman, he is the origin of the successful De la Court family. He pioneered modern thinking about the economic importance of free competition and was an uncompromising advocate of the republican form of government.
Pieter de la Court was born in Leiden, the son of Pieter de la Court the Elder and Jeanne des Planques. His parents were protestant immigrants from Flanders, who settled in Leiden around 1613 in order to be able to practise their faith and to profit from the rapid expansion of Leiden as the world centre of cloth manufacturing. Pieter de la Court the Elder was a successful cloth merchant before he arrived in Leiden. His wife also came from a family of wealthy cloth manufacturers. They had established themselves as members of the local economic elite by the time Pieter was born. The couple had three other children; Jacob (born 1617), Johanna (born 1620) and Johan (1622–1660). Johan is generally seen as the author of at least two of the books that have later been ascribed to Pieter.
De la Court studied at Leiden University and completed his education with a Grand Tour through Europe in 1641 - 1643. He went to London, Saumur (France), Geneva and Basle. The diary he kept during his journey has been preserved and was published in 1928. After returning to Leiden, De la Court entered his father's profession and set up a cloth trading firm with his brother Johan. By 1650 the firm of the two brothers had evolved into one of the leading cloth operations in.
In spite of his immigrant background De la Court was able to penetrate the social elite of Holland. He became a close friend of Johan Eleman, who was a member of Leiden's governing council and a relative of John de Witt, the de facto leader of the Dutch Republic between 1653 and 1672. In 1657 De la Court married Eleman's sister in law, Elisabeth Tollenaer, who died only one year later in childbirth. In 1660 death struck again, this time taking De la Court's younger brother and business partner Johan. Pieter was remarried in 1661, this time to Catharina van der Voort, the sister of two wealthy Amsterdam merchants and, again, a relative of John de Witt.