The English School was founded by The Sisters of the Most Precious Blood in 1945. Instruction was based on Christian values. The Ministry of Education and the National Board of Education had granted permission for the establishment of an English language school with the stipulation that all children must receive instruction also in Finnish. The school opened with an enrollment of eighteen students on October 1, 1945 in Eira on Engelinaukio 1. A permanent approval for the school was granted in 1946. The school continued to grow and new classes were added each year.

From 1945 to 1992 the Sisters were in charge of the school which is why the school is known as the “Sisters’ School”. Many remember the Sisters' genuine interest in the students’ scholastic achievements, and their motherly discipline and a loving understanding for each pupil.

1952 was an important year in the school’s history. The first five students graduated, and the construction of the new school building on Mäntytie was completed. In 1975 it was enlarged by adding a gymnasium and a library, as well as an art studio, a science laboratory and a textile handwork room.

The English School High School opened its doors in 1995, which is another significant year in the school’s history. Today, the historical tradition is still greatly valued and alive in The English School Community.