Adopted locally in 2013 following a rally to reunite survivors of the Saint Joseph Mission residential school in British Columbia, and then nationally in 2014, the sweater symbol refers to the story of one of the survivors, Phyllis Webstad.

At the 2013 gathering in William's Lake, she tells the story of how, in 1973, just before entering boarding school, her grandmother allowed her to buy a beautiful orange sweater. Unfortunately, it was confiscated when she entered boarding school, and she never saw it again. From that moment on, the color orange always reminded her that her feelings didn't matter, that no one cared about her and that she was nothing but a nobody.

From that day on, the orange sweater became the symbol and rallying point for residential school survivors in Canada. It's a symbol that's now celebrated every year on September 30, a date that wasn't chosen at random, as it's the day on which, for generations, aboriginal children were taken from their homes and forced to attend residential schools. 

Source: Canadian Encyclopedia