The department for girls was opened in the RI campus of Bras Basah Road on 4 March 1844 with 11 students, 5-day-scholars and six boarders, who were clothed, fed and instructed by the institution itself. The demand for education grew and in 1847, the school moved to RI's eastern wing, extending towards Bras Basah Road. Governor of the Straits Settlement, E.A. Blundell described RGS as "a female school designed for the education and religious training of the children of poor Protestant parents" in 1855. In 1871, the school moved into a house, the George Family's Old Mansion at the corner of Bras Basah Road. In 1879, the school separated from RI and Miss Nelson was appointed the school's first headmistress. Together with three assistants, she ran the school which had an enrolment of 77. Since then, 1879 has been officially regarded as the year of the founding of RGS.