He was born in Scotland in 1801, and was a relative of famed Alexander McKenzie. He came to America at an early age and later entered the service of the British fur companies. Little is known of his life until he and Joseph Renville formed the Columbia Fur Company. In 1827, at the time of the Columbia Fur Company joining the American Fur Company, McKenzie was the president of the former and was placed in control of the American Fur Company's interests in the Upper Missouri area. In this way, with two other men known as Laidlaw and Lamont, the Upper Missouri Outfit was formed.
McKenzie's prime target for trade was the hostile Blackfeet. Up until now, the Blackfeet had continually driven white trappers from their land. Lucky was the white trapper, of the time, who was driven out, rather than being killed and his topknot decorating the lodge or lance of one of the Blackfeet. It was a huge and dangerous undertaking that McKenzie had before him. The man who could accomplish this task could consider himself king of the fur trade.
But accomplish this near-impossible feat, McKenzie did. At the end of four years he was in control of the fur trade with posts at the mouth of the Bighorn, the Marias, and with Fort Union on the Yellowstone. It was from his Fort Union headquarters that McKenzie "ruled over an extent of country greater than that of many a notable empire in history" Indeed, McKenzie was king-at least for a while. But even kings can break rules and make big mistakes.
McKenzie was fairly well educated and it is fortunate for history that he was. The abundance of handwritten correspondence that has been left to history shows the mind of an intelligent man who had interest and concerns in world affairs. But one interest, a rule of the company, evidently was considerably disagreeable to him. In fact, and making his discretion more serious, the rule McKenzie broke was also a law that had been passed by Congress.
