Cowcaelth was likely born in 1834. He was a Nisga'a leader.

In 1867, at the age of 33, he was baptized by Revered Robert Richard Arthur Doolan as Phillip Latimer. He served as a voluntary and informal missionary among villages. Later, he became Captain of the Church Army in the 1890s at Ging̱olx (also Gingolx or Kincolith) in the Nass River valley in British Columbia, Canada.

Cowcaelth was also a skilled carpenter. He made sacred or ceremonial items as well as school and church furnishings.

Patterson, E. Palmer. “Nishga Perceptions of Their First Resident Missionary, the Reverend R. R. A. Doolan (1864-1867).” Anthropologica, vol. 30, no. 2, 1988, pp. 119–135.

Patterson, E. Palmer. “Early Nishga-European Contact to 1860: A People for ‘Those Who Talk of the Efficiency of Moral Lectures to Subdue the Obduracy of the Heart.’” Anthropologica, vol. 25, no. 2, 1983, pp. 193–219.