In May 1965, then provincial Minister of Education William Davis introduced Bill 153 which created the province´s community college system to provide a post-secondary education alternative for those not wanting or able to attend university. Colleges were to be independent of existing systems, community-based and fulfill the needs of business and industry.
In August 1966, Seneca College was officially established at its first Board of Governors meeting, chaired by Fred Minkler.
Sept. 6, 1967: Seneca opened its doors with founding President William Newnham. That first year had 852 full-time and 1,067 part-time students enrolled in 20 diploma and certificate programs. Classes were offered at a number of sites including the North York Board of Education, the Woolworth Store at Sheppard and Yonge, the Lewis Beattie Secondary School and a renovated factory at 43 Sheppard Avenue East.
- 1968: Ground was turned on a 62-acre parcel of land at Finch Avenue and Woodbine Avenue (now Highway 404). The first phase of construction created a two-storey brick building containing the college´s computer, secretarial, engineering and applied arts programs. At the same time, the Air Flight Technology Program began at Buttonville Airport. College enrolment grew to 8,667 full-time and part-time students.
- 1971: Seneca purchased Lady Flora Eaton´s King Township estate and the adjoining 650 acres. This would become Seneca´s King Campus.
- 1972: Seneca´s Sport Centre, featuring a triple gymnasium and an ice arena, opened at Newnham Campus.
- 1975: Construction of the 137,000 square-foot Garriock Hall began at King Campus.
- 1980: Seneca´s enrollment had grown to 10,412 full-time and 64,717 part-time students.
The Newnham Campus Phase One Annex was opened. A new facility at the Jane Campus was created for instruction in the metals machining, tool and die and mould making trades.
- 1984: The Board of Governors voted to rename the Finch Campus in honour of the retiring President William Newnham. The Vice-President Academic, W. Roy McCutcheon, was named his successor.
- 1988: Seneca was the first college in the province to enter into a joint articulation agreement with a secondary school. The agreement with Georges Vanier Secondary School offered academic and skills upgrading programs as credit courses for high school students.
- 1989: An extension to Newnham Campus connected Phase Three to the Sports Centre. The Student Federation Council and alumni groups pledged more than $600,000 for its construction.
- 1991: President McCutcheon announced his retirement, Senior Vice-President Stephen Quinlan was appointed Seneca´s third President.
- 1994: The province announced it would provide capital for the development of the Seneca@York Campus of advanced technology, located on the grounds of York University, and the Yorkgate Campus in the Jane-Finch area.
The Yorkgate Campus officially opened as a community-based campus in the Jane-Finch area. It offers program development based on on-going consultation with the community; a strong emphasis on skills assessment; training and career counselling; assistance with job placement, and links to local services and referral agencies.
- 1996: Seneca offered 230 programs of study. Enrolment had grown to more than 100,000 full-time and part-time students.
- 1997: Seneca International, a for-profit corporation, was approved by the provincial government. The corporation allows Seneca to take part in international business opportunities. As a separate entity, the corporation will face any financial risk from these partnerships, while the College will benefit from any financial gain.
- 1999: Seneca@York opened its doors to the first semester of students. Designed by renowned Canadian Architect Raymond Moriyama, the campus is home to Seneca´s School of Communication Arts, School of Biological Sciences and Applied Chemistry, School of Computer Studies and Centre for Professional Communications.
- 2001: Construction begins on the Ontario government funded Newnham Campus and TEL Building SuperBuild projects.
President Stephen E. Quinlan retired, Dr. Rick Miner was appointed Seneca´s fourth president.
- 2002: The provincial government granted Seneca College the ability to offer bachelor's degrees. In September, Seneca became the first college in Ontario to offer a degree program when classes begin for its Bachelor of Applied Business - Financial Services Management Program.
- 2003: Seneca offered three additional bachelor’s degree programs: Bachelor of Applied Technology - Integrated Environmental Site Remediation, Bachelor of Applied Technology - Software Development, Bachelor of Applied Technology - Flight Program.
- 2004: Seneca's TEL Building officially opened.
Seneca purchased a 10-storey office building that will become its Markham Campus.
Seneca opened its new Animal Health Facility at King Campus.
- 2005: The animated short film Ryan, produced in association with Seneca, was awarded an Oscar®.
Seneca opened its Markham Campus in September. The campus is located in the town of Markham, Ontario on 27 acres of land at the crossing point of highways 7 and 404, in one of the fastest growing regions in Canada.
- 2006: Seneca received authorization for three new degrees: Bachelor of Applied Business - International Accounting and Finance, Bachelor of Applied Business - Human Resources Strategy and Technology, Bachelor of Applied Technology - Informatics and Security.