After her husband's death in 1218, she assumed the regency for their infant son, King Henry I, but her maternal uncle Philip of Ibelin became the actual head of state administration as bailli (governor).

She married Bohemond, heir apparent to the Principality of Antioch and the County of Tripoli, but their marriage was annulled on grounds of consanguinity—they were too closely related according to canon law.

As the only surviving child of her father, King Amalric of Jerusalem, Isabella had a strong claim to rule the remnants of the kingdom along with her new husband.

[11][12] Although Alice and Philippa survived their father, the French king Philip II invested their uncle, Theobald III, with Champagne and Brie in January 1198.

[9][14] Theobald IV's position was not secure because Alice and Philippa, both born while their father was count, could challenge their uncle's posthumous son's claim to his counties.

[15] Maria Komnene conducted the negotiations for the marriage of Alice to King Hugh I of Cyprus, Aimery of Lusignan's eldest surviving son and successor, in accordance with the agreement their fathers had reached.

[15] Blanche paid part of her niece's dowry to ensure that she would stay in Cyprus rather than attempt to lay claim to Champagne and Brie.

[20] If the inquiry had been completed, Queen Maria, Alice and Philippa could have lost their claim to the Kingdom of Jerusalem, for children born to parents whose marriage was declared void were regarded as illegitimate.

[20] After Hugh I died in Tripoli on 10 January 1218, Alice assumed the regency for their infant son, Henry I, and installed her uncle Philip of Ibelin as bailli.

[26] In August that year, Pope Honorius forbade the marriage at Theobald IV's behest, emphasizing that Alice and William were closely related.

[26] According to the "Chronicle of the Holy Land" section of the Gestes des Chiprois, Alice "spent the revenues of the kingdom liberally", resulting in conflict with Philip of Ibelin.

[26][29] Pope Honorius ordered Archbishop Eustorgius of Nicosia to inquire into the legality of the marriage, probably on the request of Cypriote barons who did not want her new husband to intervene in the government of Cyprus.

[33][34] On Philip of Ibelin's initiative, the High Court arranged the coronation of the eight-year-old Henry without the Emperor's consent in 1225, drawing Frederick's ire.

[33][36] Frederick persuaded the dying Pope Honorius to delegate two new judges (the Latin patriarch of Jerusalem Gerold of Lausanne and the bishop of Acre Jacques de Vitry) to investigate the marriage of Alice and Bohemond, accusing Eustorgius of partiality in the couple's favour.

[40] Frederick made Aimery Barlais, Gavin of Chenichy, Amaury of Beisan, Hugh of Gibelet and William of Rivet baillis of Cyprus without Alice's consent before departing for Italy in May 1229.

[38] In autumn 1229, Alice arrived in Acre, whereupon she laid claim to the Kingdom of Jerusalem against the infant Conrad, son and successor of her niece Isabella II.

[44][43] She appeared before the High Court of Jerusalem declaring that Conrad had forfeited his right to the kingdom as he had failed to personally take possession of it within a year and a day of the death of his mother, as required by a local law regarding fiefs inherited by a non resident heir.

The members of the High Court approached Philip of Novara, a noted jurist, for a legal opinion, and he concluded that Frederick could no longer administer the Kingdom of Jerusalem on his son's behalf.

[50][52] Novara also argued that Alice and her husband were entitled to rule the kingdom as regent for the absent Conrad because she was his closest relative who lived in the Holy Land.

[53] The members of the High Court, the representatives of the clergy, the Military Orders and the Italian communities held a joint assembly where Alice and Ralph of Nesle were proclaimed regents on 5 June.

[53][54] Ibelin and Montfort also refused to transfer Acre to him and Alice, causing Nesle to depart the Holy Land in anger, stating that he was only a "shadow” ruler in the kingdom.

[55] Alice nonetheless exercised royal prerogatives: she annulled grants and appointments that Frederick had made after the death of Queen Isabella II, and Philipp of Novara received a money-fief of 1,000 bezants from her.

[57] When Alice died in 1246, her son, Henry of Cyprus, succeeded her as regent of the Kingdom of Jerusalem although her younger half-sister Melisende also claimed the regency.