In 1870, Lord Mayo, the then Viceroy and Governor General, came to Ajmer, where in a Darbar, before the Chiefs of the ruling Princes of Rajputana, he expressed his desire to set up a 'Raj Kumar College' in Ajmer, "devoted exclusively to the education of the sons of Chiefs, Princes and leading Thakurs."
It is interesting to point out that several generations of the descendants of many present at that Darbar have since continued to study at Mayo College.
The College was opened in October 1875, with Sir Oliver St.John as the first Principal and one boy, Maharaja Mangal Singh of Alwar.
The Main Building was completed in 1885 and was designed by Major Mant. Some of the greatest changes in the school were brought about by Mr.Stow who was the Principal from 1931-1943. In the same year, the Viceroy ceased to be the President of the General Council. This body was in future presided over by a ruling Prince elected by the council.
Today, students from all walks of life, study in this prestigious school and make complete use of the many facilities offered.