According to the Netherlands Institute for Art History (RKD), he was one of five children of the painter Jacob Willemszoon de Wet.
In 1684 de Wet returned to work at Holyrood and signed a contract with Hugh Wallace, the Royal Cashkeeper, on 26 February which bound him to produce, for £120 per annum and within the period of two years, 110 portraits of Scottish monarchs from the legendary King Fergus to the reigning Charles II.
[3] The completed set (a portrait of James VII was also added upon his accession) was hung in the Great Gallery of Holyroodhouse and 97 are still on display today.
Eleven of the portraits have disappeared, possibly destroyed by Lieutenant General Henry Hawley’s Dragoons, who were stationed at Holyrood after their defeat by Bonnie Prince Charlie at Falkirk in 1746.
[3] After completing his royal portrait series, and after a further two years in Scotland which included painting 34 scenes from the Life of Christ for Patrick Lyon, 3rd Earl of Strathmore and Kinghorne on the ceiling of the Chapel of Glamis Castle, de Wet again returned to Amsterdam.