"The names Og, Gog and Magog are mentioned in the Old Testament of the Bible. Og was a giant King of Bashan, conquered by Moses. Gog was a prince, and Magog was the land he came from (Ezekiel: 38, 39). Gog and Magog are also mentioned in the Book of Revelation: chapter 20. Robert Young, author of "Analytical Concordance to the Bible" (1893) gives a meaning of Gog as "high, mountain." Magog was the second son of Japheth (Genesis: chapter 10). An English myth relates that Gog and Magog were the last of a giant race and were captured and brought to England. Early Celtic mythology also mentions these giants. It is possible that this mountain was named from one of these origins."
Source: Place Names of Alberta, Alberta Geographical Names Program and Friends of Geographical Names of Alberta Society, University of Calgary Press, 4 volumes, 1991-1996.