Kennedy was born in 1805 and described in Hudson's Bay Company records as 'Native' as his mother, Aggathas, was part Cree. He received medical training in Edinburgh, Scotland and entered service of the Company in 1829 as a surgeon on the Isabella. He served as a surgeon at several Forts on the Northwest Coast, including Fort McLoughlin, Fort Durham and Fort Simpson where, in 1850, he was also Chief Trader. Dr. Kennedy married the daughter of a prominent Tsimshean chief in Fort Simpson where he resided throughout much of the late 1840s and early 1850s and where he was regarded as a valuable intermediary between the indigenous people of the region and the traders. He retired to Victoria in 1856 and was elected to the first House of Assembly for Vancouver Island in the same year. He died in Victoria in 1859.