In 1746, Hume returned to London after touring Europe as tutor and caretaker of the mad Marquess of Annendale. He was not sure what was next in his life. He was already 35 and somewhat ashamed of not having yet made a career for himself. He resolved to return to Scotland, but at the last minute he received an unexpected invitation to serve in a military expedition to Canada. The invitation came from Lieut.-General James St Clair, a distant relative of Hume whom he had recently met. The opportunity hit Hume at just the right time, and he wondered if this was the beginning of a career in the military. 

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