Alphonse I was the son of Count Raymond
IV by his third wife, Elvira of Castile. He was born
in the castle of Mont-Pelerin, Tripoli, in modern Lebanon.
He was surnamed Jourdan because he was baptised in the Jordan
River.
His father died when he was two years old and he remained under the guardianship of his cousin, Guillaume Jourdain, Count of Cerdagne (d. 1109), until he was five. He was then taken to Europe and his brother Bertrand, Count of Toulouse and of Tripoli, gave him the County of Rouergue. Aged nine years he succeeded to the County of Toulouse and Marquisate of Provence on Bertrand's death in 1112. Toulouse was taken from him by William IX, Duke of Aquitaine and Count of Poitiers, two years later in 1114. William claimed it by right through his wife Phillipa of Toulouse, daughter of William IV of Toulouse. He recovered a part of his County in 1119, but continued to fight for the rest of his possessions until about 1123. Finally successful, he was excommunicated by Pope Callixtus II for having expelled the monks of Saint-Gilles, who had allied themselves with his enemies.
He next fought for the sovereignty of Provence against Raymond Berenger III. The war end in an amicable agreement in September 1125. Under it Alfonse-Jourdan became absolute master of the regions lying between the the Pyrenees and the Alps, from the Auvergne and the sea. His ascendancy is acknowledge to to have been good for the country. During a period of fourteen years art and industry flourished.