Coinciding with the National Day of Mourning, Un-Thanksgiving Day is a similar event held on Alcatraz Island in San Francisco Bay. Beginning in 1975, Un-Thanksgiving Day serves to commemorate the 1969 Occupation of Alcatraz and promote Native American rights.
Protesting Thanksgiving Day and its colonialist sentiments, Un-Thanksgiving Day calls to light the genocide and destruction of Native American society and life that began upon European settlement of North America. Challenging the traditional narrative of Thanksgiving Day, Un-Thanksgiving Day serves to dispel the notion that European arrival to North America was something worth celebrating.