Humbert I of Viennois explained

Humbert I of Viennois (c. 1240 – 12 April 1307) was baron of la Tour-du-Pin and then also became, by his marriage, dauphin of Viennois. He was the son of Albert III, baron of la Tour-du-Pin, and of Béatrice de Coligny (herself the daughter of Hugh I, lord of Coligny and of Béatrice d'Albon, dauphine of Viennois).

In 1294, Humbert became a vassal of King Philip IV of France in exchange for £500 annual pension, which would give impetus to the acquisition of the Dauphiné, by King Philip VI of France, fifty years later.

In September 1273 Humbert married Anne of Burgundy (daughter of Guigues VII of Viennois) – their nine children were:

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