Erasmus of Rotterdam, also known as Desiderius Erasmus, was a Dutch humanist and scholar who lived during the Renaissance period. He was an influential figure in the development of Christian theology and philosophy, and is best known for his works 'In Praise of Folly' and 'The Handbook of the Christian Soldier'. He was also a prolific writer of letters, and his correspondence with Thomas More is considered to be one of the most important documents of the period. Erasmus was a proponent of religious tolerance and reform, and his works had a major influence on the Protestant Reformation.