McDonogh School was founded on November 21, 1873, when 21 poor boys from Baltimore City arrived on the 835-acre campus, approximately 15 miles northwest of Baltimore's harbor, where they would live, work, and learn. The first principal of the school, Col. William Allan, organized the boys into a semi-military program, and the school became a military, boarding, farm school for poor boys for most of the next century.
Major milestones in McDonogh’s structure include the first pay students admitted in 1922 and the first day (non-boarding) students admitted in 1927. The first African-American student was admitted in 1959. The semi-military program was abolished in 1971, and the first female students enrolled in 1975.
Today, McDonogh is a PK-12, non-denominational, coeducational, college preparatory day school that also offers a five-day residential life option for Upper School students. The McDonogh Character Compass, the school's diversity, equity, and inclusion, and the LifeReady Academic Plan guide current students to become resilient, lifelong learners of strong character.