The villa where the headquarters of the Istituto Marymount was built in 1910, on land that is located in Via Nomentana, above the ancient catacombs of St. Agnes, was initially a country residence of a noble family, the site of the Embassy Russia before the revolution and was finally purchased by the Sambuy Counts and became their private residence.
When Mother Butler, founder of the Marymount schools, came to Rome in 1929 to pay homage to Pope Pius X, who asked her to establish a branch of the Congregation of the Sacred Heart of Mary (Religious of the Sacred Heart of Mary) in the eternal city. This Villa was chosen because of its proximity to the Basilica of St. Agnes. This is where the first sisters were sent to begin the school.
The Boarding School hosted young girls coming from well-to-do families, to prepare them for entry into adult society. Over the years the school became bigger and after the Second World War, after a period of great difficulty, the process to obtain legal recognition began, which was finally obtained in obtained in 1962.

During the Eighties, enrollment increased and the school began welcoming children to four levels of edication: early childhood, primary, middle school and high school. Male students were also accepted. The high school was later closed in 1998 and since then all educational efforts are aimed at offering a full bilingual program for early childhood, primary and middle school levels. In 2001 the school was officially recognized by the Ministry of Education and the number of pupils has grown year after year, until reaching the current number of 645 pupils. The school falls under the the supervision of the Attorney General of the Sisters of the Sacred Heart of Immaculate Virgin Mary and the campus is owned by the Congregation.