Louis I, Prince of Monaco was Prince of Monaco from 1662 until 1701.
Louis Grimaldi was the elder son of Prince Hercule of Monaco and Maria Aurelia Spinola. In 1662 Louis succeeded his grandfather Honoré II as Prince of Monaco. In 1666 he distinguished himself at the Four Days' Battle between the English and Dutch fleets. On 5 July 1668 he took the oath to King Louis XIV of France in the Parlement on account of being Duke of Valentinois and a Peer of France. He was made a knight of the French royal orders on 31 December 1688.
In 1699 Louis XIV sent Louis to Rome as ambassador extraordinary. There on 19 December he presented the insignia of the Order of the Holy Spirit to James Louis and Alexander Benedict Sobieski, the two sons of King John III of Poland. Louis remained in Rome, where he died 3 January 1701. His remains were transported back to Monaco.