Desiderius Erasmus is reported to have been born in Rotterdam on 28 October in the late 1460s. He was named after Saint Erasmus of Formiae, whom Erasmus's father Gerard personally favored. A 17th-century legend has it that Erasmus was first named Geert Geerts (also Gerhard Gerhards or Gerrit Gerritsz), but this is unfounded. A well-known wooden picture indicates: Goudæ conceptus, Roterodami natus (Latin for Conceived in Gouda, born in Rotterdam). According to an article by historian Renier Snooy (1478–1537), Erasmus was born in Gouda.
The exact year of his birth is controversial but most agree it was in 1466. Evidence confirming the year of Erasmus' birth in 1466 can be found in his own words: fifteen out of twenty-three statements he made about his age indicate 1466. He was christened "Erasmus" after the saint of that name. Although associated closely with Rotterdam, he lived there for only four years, never to return. Information on his family and early life comes mainly from vague references in his writings. His parents were not legally married. His father, Gerard, was a Catholic priest and curate in Gouda. Little is known of his mother, although her known name was Margaretha Rogerius (Latinized form of Dutch surname Rutgers) and she was the daughter of a doctor from Zevenbergen. She may have been Gerard's housekeeper. Although he was born out of wedlock, Erasmus was cared for by his parents until their early deaths from the plague in 1483. This solidified his view of his origin as a stain and cast a pall over his youth.
Erasmus was given the highest education available to a young man of his day, in a series of monastic or semi-monastic schools. At the age of nine, he and his older brother Peter were sent to one of the best Latin schools in the Netherlands, located at Deventer and owned by the chapter clergy of the Lebuïnuskerk (St Lebuin's Church), though some earlier biographies assert it was a school run by the Brethren of the Common Life. During his stay there the curriculum was renewed by the principal of the school, Alexander Hegius. For the first time ever Greek was taught at a lower level than a university in Europe, and this is where he began learning it. He also gleaned there the importance of a personal relationship with God but eschewed the harsh rules and strict methods of the religious brothers and educators. His education there ended when plague struck the city about 1483, and his mother, who had moved to provide a home for her sons, died from the infection.