First found in Brittany, where they are recorded as an ancient family with lands, manors and estates.

France finally gave land incentives for 2,000 migrants during the 1700s. Early marriage was encouraged in New France, and youths of 18 took fourteen-year-old girls for their wives. The fur trade was developed and attracted migrants, both noble and commoner from France. 15,000 explorers left Montreal in the late 17th and 18th centuries, leaving French names scattered across the continent. The search for the Northwest passage continued. Migration from France to New France or Quebec, as it was now more popularly called, continued until 1759. By 1675, there were 7000 French in Quebec. By the same year the Acadian presence in Nova Scotia, New Brunswick and Prince Edward Island had reached 500. In the treaty of Utrecht, the Acadians were ceded by France to Britain in 1713. In 1755, 10,000 French Acadians refused to take an oath of allegiance to England and were deported. They found refuge in Louisiana. Meanwhile, in Quebec, the French race flourished, founding in Lower Canada, one of the two great solitudes which became Canada. Many of this distinguished family name Cadiou were prominent in social, cultural, religious and political affairs in France and New France. Amongst the settlers in North America with this distinguished name Cadiou were François Cadieu, 17; who settled in Louisiana in 1719; Pierre Cadieux, who married Marguerite Menard in 1697 in Boucherville, Quebec; Jacques Cadieux, who married Marie Viau in 1731 in Longueuil, Quebec.

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