[2][3] Pope Innocent II named him cardinal in December 1138, initially as cardinal-deacon of San Adriano, then (in May 1141) as cardinal-priest of Santa Prassede and sent him as legate to France.

[4] Allucingoli then served as a member of the court of arbitration regarding the Terre Matildiche, (lands formerly held by the late Countess Matilda of Tuscany to which the Church and the Emperor both laid claim), but which reached no definite conclusion.

He lived at Rome from November 1181 to March 1182, but dissensions in the city compelled him to pass the remainder of his pontificate in exile, mainly at Velletri, Anagni and Verona.

Lucius freed the king from all ecclesiastical censures incurred under his predecessor and agreed to a compromise by which Hugh was raised to the see of St. Andrews and John became Bishop of Dunkeld.

[5] The controversy over the succession to the inheritance of the Countess had been left unsettled by an agreement of 1177, and the Emperor proposed in 1182 that the Curia should renounce its claim, receiving in exchange two-tenths of the imperial income from Italy, one-tenth for the Pope and the other tenth for the cardinals.

Lucius consented neither to this proposition nor to another compromise suggested by Frederick I the next year, nor did a personal discussion between the two potentates at Verona in October 1184 lead to any definite result.

In pursuance of his anti-imperial policy, Lucius declined in 1185 to crown Henry of Hohenstaufen as Frederick I's destined successor, and the breach between the Empire and the Curia became wider on questions of Italian politics.

In November 1184 Lucius held a synod at Verona which condemned the Cathars and Paterines, Waldensians, Josephines, Pasagians and Arnoldists, and anathematized all those declared as heretics and their abettors.