St Patrick's College is blessed with a threefold tradition that began in 1873 when the Presentation Sisters taught pupils at their convent in Launceston. With its small beginning, Sacred Heart College was established. The growing need for the education of Catholic children in Launceston was further met by the arrival of the Christian Brothers and the opening of St Patrick's College at York Street in 1919. The third branch of this educational tradition in Launceston began with the establishment of St Thomas More's School under the auspices of the Sisters of St Joseph in 1938. The schools grew as the Religious Orders made a significant contribution to the Catholic community of Launceston. Despite the hardships of earlier years, the Catholic community of Launceston continued to invest in the education of their children. In 1958 the Christian Brothers opened a new campus for St Patrick's College at Prospect Vale. This became a secondary College for boys.
Further financial strain and the challenges of a more extensive curriculum led to an amalgamation of the two secondary girls’ Colleges. In 1978 Sacred Heart and St Thomas More's joined to form Marian College. Finally, in order to provide a continued high standard of education for the Catholic families of Launceston, a further amalgamation of schools occurred when St Patrick's College and Marian College joined to create the new coeducational secondary College which is St Patrick's today. This major shift in Catholic education took place at the beginning of 1984 heralding a new era of enthusiasm, vision and endeavour. In 1998, the Year 7 class left the Newstead campus and came to join the other classes at Prospect, completing the amalgamation process to a Catholic College on a single campus.
In 2008, the decision was made by the Board and Governing Council to restructure the College into Middle School (Year 7 and 8), Year 9 (Croagh Patrick) and Senior School (Years 10-12). The decision was made in order to more fully meet the needs of students in the 21st Century and provide a challenging and supportive learning environment at each stage of development through secondary education. Purpose built facilities for Year Nine students opened in 2012. Renovations of the Middle and Senior schools are planned for subsequent years. What had begun in a very humble way with the three Religious Orders of the Presentation Sisters, the Christian Brothers and the Sisters of St Joseph is now being carried on enthusiastically by a group of professional lay teachers committed to the ongoing vision and ethos of Catholic education. The College crest is dominated by the number three reflecting the earlier history of the emerging of the three Colleges over time. The three flames at the centre of the crest represent the influence of the Holy Spirit on the three founding orders, the Christian Brothers, the Presentation Sisters and the Sisters of St Joseph. The chain in the crest symbolises the motto of our College, 'Strength through Faith and Knowledge'. St Patrick’s, the Patron of our College continues to inspire our community. Patrick had a great love of people, a great love of God and a great love of creation. These attributes inspire our students to become involved in the unfolding story of humanity and to make their personal contribution to the development of society.