Constantijn l'Empereur (July 1591 – June 1648) was a prominent Dutch Hebraist, a distinguished Orientalist and doctor of theology.
He was born in July 1591 in Bremen, Germany, to where his parents had fled from the Southern Netherlands, modern Belgium, after his grandfather was executed by the Council of Troubles.
After eight years, in 1627 he was made professor of Hebrew and Aramaic at the University of Leyden on which occasion he delivered an harangue on the dignity and utility of the Hebrew language and it was his constant endeavour to diffuse a knowledge of that language and of the Arabic and Syriac among his countrymen that they might be the better enabled to combat the objections of the Jews to the Christian religion.
l'Empereur's edition of Rabbi Benjamin of Tudela Itinerary was the basis for a popular German and French translation in the 17th and 18th Century.
He offered at one time to superintend the printing of a Talmudical dictionary in Holland and endeavoured to bring the younger Buxtorf to Leyden who had undertaken to defend the vowel points against Louis Cappel.