Amadeus was the son of Aymon I of Geneva (the preceding count) and of Ida de Faucigny.

During his lifetime Amadeus I added the city of Annecy to his territories, thereby increasing the power of his County.

He also sought the protection of the House of Zähringen, after losing the rights to the dioceses of Sion, Lausanne and Geneva.

Emperor Frederick Barbarossa in 1156 granted the rights to Berthold IV of Zähringen instead.

In 1178 Amadeus donated the vineyards and tithes collected in Bossey to the canons of the chapter of St. Pierre Cathedral in Geneva.