Jan Mostaert was a Dutch Renaissance painter who is known mainly for his religious subjects and portraits. One of his most famous creations was the Landscape with an Episode from the Conquest of America.

There are very few details about the life of Jan Mostaert that are known with any certainty. The traditional account of his life was based on the biography written by the 16th century Flemish artist and art historian Karel van Mander and included in his Schilder-boeck, published in Haarlem in 1604. Modern scholarship questions many of the assertions about the life of Mostaert made by Karel van Mander.

One of these is van Mander's assertion that he was appointed 'painctre aux honneurs' ("painter with honors") by Margaret of Austria, the governor of the Habsburg Netherlands; it does not seem that he became Margaret's court painter, although there are two mentions of him in her accounting records. Recent art historians think he probably worked in the provincial town of Haarlem, some way from the larger cities of the southern Netherlands, for all or most of his career.

Mostaert was born in Haarlem as the son of a mill owner also named Jan and Alijt Dircx. Karel van Mander stated that Mostaert was a pupil of Jacob van Haarlem, the artist who painted the altarpiece of the Carrier's guild in the St. Bavochurch of Haarlem.

Mostaert's name first appeared in city records in 1498, the year he bought a house in his birthplace. The artist is documented in Haarlem almost every year from 1498 to 1552 except for a ten-year period between 1516 and 1526. In 1500 Mostaert was commissioned to paint the shutters for a receptacle housing the relics of Saint Bavo in the Groote Kerk, Haarlem. From this date he began to be listed in the records of the Haarlem Guild of St. Luke, and continued to be frequently listed until 1549. He became deacon of the painters' guild in 1507, and again in 1543 and 1544.

Margaret of Austria, the governor of the Habsburg Netherlands, appointed Mostaert 'painctre aux honneurs' (painter with honors) in March 1518. Van Mander wrote that he worked for Margaret for 18 years and was commissioned by her to create portraits. As there is no evidence that he was her court painter, there is no reason to trust Van Mander's statement that he worked at Margaret's court in Mechelen for 18 years. He is missing from the records in Haarlem for a string of only 10 years, and only two documents from 1519 and 1521 give any mention that he was working at her court at the time.

The current view of art historians is that Mostaert worked his entire life in Haarlem. Since his house was rented to others in 1553 and payments to him stopped around Easter 1553, it is believed that he died early in 1553 or perhaps late in 1552. In 1554 his name was crossed out from the list of members of the Haarlem Guild of St. Luke.

Mostaert married Angnyese (Agnes) Martijnsdr, the widow of Claes Claesz Suycker, before 8 June 1498. His wife died before July 1532. Mostaert was commercially successful and owned multiple houses in Haarlem.

Van Mander states that Mostaert had a son who was a common painter. It is no longer believed by art historians that Frans Mostaert and Gillis Mostaert were the grandsons of Jan Mostaert.