Clementina Trenholm Fessenden, (4 May 1843 – 14 September 1918), was born at the village of Trenholm, Canada East and died at Hamilton, Ontario, author, social organiser. Also, mother of Reginald Fessenden, the radio pioneer. Buried in St John's Anglican cemetery, Ancaster, Ontario.
Educated in Montreal schools, she grew up in a home where loyalism and devotion to British traditions were strong. At twenty-one she married the Reverend Elisha Joseph Fessenden, a Canadian-born Church of England clergyman. The family moved to Fergus, Ontario, and later to Chippawa, Ontario, on the banks of the Niagara River. There, she raised her four sons and honed her writing skills as one of the first editors of the Niagara Women's Auxiliary Leaflet. In 1893, Elisha accepted the position of rector at St John's Anglican Church in Ancaster, Ontario.
Always trying to find ways to strengthen Canada's links to the British Empire, Clementina identified herself both physically and spiritually with Queen Victoria. She dressed in mourning black like the widowed Queen after her own husband died in 1896. She was responsible for introducing Empire Day in Canadian schools, first in Dundas, Ontario in 1898 on the last school day before May 24, Queen Victoria's birthday. It was celebrated more widely each year and then instituted in England in 1904 by Lord Meath. A typical Empire Day in Canadian schools occupied the entire day and included inspirational speeches by trustees and songs such as The Maple Leaf and Just Before the Battle.
A bronze plaque was installed in her memory on the wall of St John's Anglican Church in 1929, and a monument was placed by her grave in the churchyard which reads "Clementina Fessenden, Founder of Empire Day".