Desiderius Erasmus Roterodamus (October 28, 1466 – July 12, 1536), sometimes known as Desiderius Erasmus of Rotterdam, is a Dutch Renaissance humanist and a Catholic priest and theologian.

His scholarly name Desiderius Erasmus Roterodamus comprises the following three elements: the Latin noun desiderium ("longing" or "desire"; the name being a genuine Late Latin name); the Greek adjective ἐράσμιος (erásmios) meaning "desired", and, in the form Erasmus, also the name of a St. Erasmus of Formiae; and the Latinized adjectival form for the city of Rotterdam (Roterodamus = "of Rotterdam").

Erasmus is a classical scholar who writes in a "pure" Latin style and enjoys the sobriquet "Prince of the Humanists."

He has been called "the crowning glory of the Christian humanists."

Using humanist techniques for working on texts, he prepares important new Latin and Greek editions of the New Testament.

These raise questions that will be influential in the Protestant Reformation and Catholic Counter-Reformation.

He also writes The Praise of Folly, Handbook of a Christian Knight, On Civility in Children, Copia: Foundations of the Abundant Style, Julius Exclusus, and many other works.

Erasmus lives through the Reformation period and he consistently criticizes some contemporary popular Christian beliefs.

In relation to clerical abuses in the Church, Erasmus remains committed to reforming the Church from within.

He also holds to Catholic doctrines such as that of free will, which some Protestant Reformers reject in favor of the doctrine of predestination.

His middle road approach disappoints and even angers many Protestants, such as Martin Luther, as well as conservative Catholics.

He dies in Basel in 1536 and is buried in the formerly Catholic cathedral there, recently converted to a Reformed church.