The school was founded by the Reverend Thomas Langhorne in 1827. Langhorne came from Crosby Ravensworth in Westmorland. He named the school for Loretto House, his then home, which was itself named for a medieval chapel dedicated to Our Lady of Loreto which had formerly stood on the site of the school. The school was later taken over by his son, also Thomas Langhorne. The last link with the Langhorne family was Thomas' son John, who was a master at Loretto from 1890 to 1897, and later headmaster at John Watson's Institution. Loretto was later under the headmastership of Dr. Hely Hutchinson Almond from 1862 to 1903.