His childless paternal uncle, Count Philip I of Savoy, died in 1285.[4] Meanwhile, earlier, in 1282, his elder brother, Thomas III of Piedmont, had accidentally died in 1282. Philip's will charged his niece Eleanor of Provence and her son Edward I of England with the inheritance of Savoy. Amadeus was awarded the County of Savoy, and in order to diminish family rivalry, his younger brother Louis was awarded the new Barony of Vaud becoming Louis I of Vaud.[5]
Through his marriage to Sybilla, Countess of Bugey and Bresse, he was able to incorporate these Burgundian districts into his states. Later expansion saw his dominions further increased. On 1 October 1285, Amadeus was declared protector of Geneva after negotiations with the Bishop of Geneva. The hereditary title belonged to Amadeus II, Count of Geneva who was in conflict with the Bishop.
In 1287 Amadeus besieged the castle of Ile in the Rhône near Geneva and captured it after fourteen weeks.[6] In 1295, Amadeus acquired the fortress at Chambéry from its previous owner Hugh of La Rochette.[citation needed] He brought Georges de Aquila, a student of Giotto from Florence, to his court. Georges decorated the castle with paintings, carved wood, and frescoes. He worked there for the Savoyards until he died in 1348.[7]
Amadeus as one of the combatants defeating the Torriani revolt in Milan (12 February 1311)
The eventual recovery of Lyon by the kings of France alerted Amadeus to their expansionistic tendencies towards the regions by the Alps. He sought a powerful ally against potential hostility in the German king Henry VII, who was married to Margaret of Brabant, the sister-in-law of Amadeus. Amadeus accompanied Henry in his Italian campaign of 1310–1313, which culminated in Henry's coronation as Holy Roman Emperor on 29 June 1312. As a reward for his service, Amadeus received the title of Imperial Count, imperial vicar of Lombardy, and the lordships of Asti and Ivrea. Henry also elevated Aosta and Chablais to duchies, though they remained a part of the realm of Savoy.[9]
He first married Sybille de Baugé, daughter of Guy I Damas de Baugé, Baron of Couzan (c.1230–1269) and Dauphine de Lavieu,[10] and had eight children by her:
Beatrice of Savoy (*1291–1294), in 1291 fiancée promises to marriage count William III of Geneva, eventually contract annulled, William married her younger sister Agnes.[12]
^The County of Geneva, by Pierre Duparc, (text in French: "Le comté de Genève"), (IXe-XVe siècles), t. XXXIX, Genève, Société d’histoire et d’archéologie de Genève, coll. « Mémoires et documents » (réimpr. 1978) (1re éd. 1955), 621 p. (lire en ligne archive), p. 244. Geneva, Switzerland, 1978.