As befitted a growing industrial town, Lurgan had a strong educational establishment from the mid 19th Century. The opening of the Model School in 1863 had been the culmination of a period of sustained growth in the Primary Sector. However, the town had no soundly established secondary school, which must have been regarded as a serious short-coming in a middle-class interest. One of the town's leading citizens at the time, Samuel Watts, joint owner of one of the breweries, provided in his will for the endowment of such a school, which was to provide an English, Classical and Agricultural education for boys.
Watts died in February 1850, and the endowment, when it was established, amounted to some £9000. This was to be invested, and the accrued interest used to build the School. It was not until December 1872 that the Trustees considered they had sufficient money to proceed. The School commenced business in a house in Market Street during March 1873, the first Headmaster being Mr. E. Vaughan Boulger, of Dublin. The School buildings themselves, constructed on a site in the townland of Brownlowsderry, were not completed until August 1873, and were officially opened in October of that year.
Boulger left Lurgan in December 1875, to be replaced by Mr. W. T. Kirkpatrick from R.B.A.I. in Belfast. Under Kirkpatrick the school prospered academically and numerically, although not financially. On Kirkpatrick's retirement in 1899, Mr. James Cowan, of Manchester G.S. took over the principalship. Under Cowan, the school faced problems of declining numbers, although he was responsible for the introduction of Science teaching in 1905. Another major development was the admission of girls in 1918. Cowan retired in 1922, leaving a school of under thirty pupils.
The new Headmaster was Mr. V. M. Harper, from Campbell College. He presided over a major expansion in the school. Two major building projects (in 1925 and 1929) coupled with an amalgamation with the Lurgan High School for Girls (1925) transformed the College from a struggling thirty pupil school to a thriving one hundred and fifty pupil establishment. The 1947 Education Act further increased enrolments and led to an increasing dependence on temporary buildings. In 1952 Harper retired, to be replaced by his vice-principal, Mr. J. Trewsdale. Under Mr. Trewsdale the school ceased to be an independent, endowed school, (the endowments were then inadequate for the needs of the College) and became a County Grammar School. A series of building programmes beginning in 1955 and lasting until 1969 saw the provision of a modern suite of buildings well equipped to meet the needs of the area.
In 1960 the new city of Craigavon was developing and with it a radical reform of education provision in the area. The Dickson Plan introduced a modified two-tier system, based on the Leicestershire Plan. The College became a Senior High School under this scheme. Mr. Trewsdale retired in 1978 and was replaced by Mr. N. Eccles from Campbell College. The school suffered, in common with most other schools in Ulster, from a sharp decline in numbers in the early 80's but this has been reversed in recent years, the present population being 418.
Mr Eccles retired in 1988 and was replaced by Mr W. D. Johnston, the second old boy of Royal School Dungannon to become Headmaster of Lurgan College. The Johnston era was characterised by an increase in pupil and staff numbers and a steady improvement in pupil performance in public examinations. The rise in pupil numbers in the senior school, however, was not reflected unfortunately in the Preparatory Department which closed in 2004. In his years as Headmaster Mr Johnston skilfully oversaw the introduction of GCSEs, Curriculum 2000 (changes in sixth form curriculum), Classroom 2000 (ICT provision) and the Local Management of Schools programme which delegated to the school overall responsibility for the spending of its own budget. Working with his Board of Governors, Mr Johnston played a significant role in planning and bringing to fruition the impressive renovation of the school's reception area which was officially opened in March 2005. His retirement in 2005 coincided with the decision of Mr Cyril Johnston, Chairman of the Board of Governors, to retire from the Board after 35 years of sterling service to the school.
Mr Johnston was succeeded by a third Royal School Dungannon old boy, Mr T. D. Robinson, who had previously been Vice Principal at Banbridge Academy.