The School history dates back to 1864. Fort Girls' Mission High School was founded by Ms Augusta Mary Blandford, an English missionery and a strong worker of Indian Female Normal School and Instruction Society, with the permission of Ayyillam Thirunal Rama Varma, then ruler of erst while Travancore.
Her aim was to liberate the girls from being trapped in the interior of their homes, giving them education. A large disused palace in the Fort was set apart for a Girls’ School, which was opened in November 1864, with the consent of the then Maharaja, His Highness Shri. Rama Varma and Diwan Shri T Madhava Rao.
In 1880 the Church of England members of the Indian Female Normal School and Instruction Society founded the Church of England Zenana Mission. Miss Blandford went with them and carried her school with her. The school was first called as Vadakke Kottaram Pallikudam and later came to be known as Zenana Mission School. The school building that we see today was constructed during the time of Ms. Cocks. In August 1914, the then Governor of Madras, Lord Pent Lent inaugurated the building. In 1946, the Government of Kerala took over the Primary school and in 1951 the primary wing was shifted to its own new building. In 1951, High school status' was accorded to the institution. The last missionary Ms. Doss became the first Headmistress of the High School. It can be presumed that the organised activities launched by Ms. Doss and the parents of the school motivated the emergence of the Parent Teacher Associations in schools in Kerala
The first Headmaster of the Primary School was Shri. M.J. Jones and Smt. Saramma Philip Oommen became the first Headmistress of the 'High School. For 4 years continuously since 1946, one class each of the Fort U.P.G.S was held in the school premises. When Ms. Doss called it a day her mission activities, and was about to leave for England permission from the Govt was obtained to change the name of school and thus it become known as Fort Girls Mission School:. Furthermore the school located in the centre of ancestral temples of the orthodox Brahmins, was able, within a short period of time, to secure the faith of the populace around and they enrolled their children and it paved the growth and development of the school. Shri T. Madhavarao's daughter Kaveri Bhai and his niece Ambu Bhai were the first students of the school.
The school, which began with just 4 students, has now about 800 students, 30 teachers and 4 non-teaching staff.