Nothing is known of his early life except that he was of English parentage. The conjecture of an early-20th-century biographer (Williams) that he was born at Poole, Dorsetshire is not supported by any evidence. Other accounts state that he came from Devonshire. John of Hexham's continuation of the history of Symeon of Durham, written within half a century of Pullen's death, asserts that king Henry I of England offered him a bishopric which he refused, being devoted to the study of philosophy.
His early education was received in England, but during the troubles which began with the accession of King Stephen in 1135 he seems to have gone to Paris to continue his life of study in peace there. According to other accounts, he completed his education at Paris, where he subsequently lectured before returning to Oxford to teach. At Oxford he was one of the first masters whose names have been recorded. He opened schools there and taught without exacting fees; he is said to have supported many scholars at his own expense and to have been largely instrumental in fostering the growth of the Oxford schools. If these traditions are true, albeit that they rest on the statements of later writers, it would seem more probable that they happened during the reign of Henry I, when he refused to accept the bishopric offered. He was certainly Archdeacon of Rochester in 1134, and was absent from England for a notable time within the next few years, for at some date prior to 1143 he seems to have been in trouble with his bishop for being absent so long from his duties. This appears from an undated letter of St. Bernard addressed to the Bishop of Rochester, in which the saint makes his excuses for detaining Pullen in Paris "on account of the sound doctrine which is recognized in him." In the same letter he blames the bishop for seizing the archdeacon's goods, and he begs that Pullen may stay longer in Paris where he is necessary. Though Bishop Stubbs (op. cit.) has thrown doubt on the identity of this Archdeacon Robert Pullen with the cardinal Robert Pullus (also called Pullen), the statements of St. Bernard's biographer, William Abbot of Theodoric, and the Oseney Chronicle justify the identification.
While in Paris, Pullen taught logic and theology with great success. Among his pupils was John of Salisbury, who describes him as a man commended both by his life and his learning, in 1141 or 1142. In 1143 he is still described as Archdeacon of Rochester and in or about that year he probably went to Rome on the invitation of Innocent II, who died in September of that year, but Pullen found favour with the new pope, Celestine II, who created him a cardinal (Ciaconius). The Oseney chronicler, however, states that he was called to Rome by Lucius II who succeeded Celestine in 1144. Certainly Pope Lucius appointed him Chancellor of the Holy Roman Church, an office which he was discharging through 1145 and 1146. Whether by Lucius or Celestine, he was a cardinal by around 1144. When St. Bernard's disciple, Eugenius III, became pope in 1145, the saint wrote a letter to Cardinal Pullen begging him to console and counsel the new pontiff.
His date of death is uncertain; he died in or after 1146.
As a theologian Cardinal Pullen used all his influence against the teaching of Abelard, and embodied his doctrine in his work Sententiarum Logicarum Libri VIII. In this treatise he was breaking new ground, being one of the first teachers to compile a book of "Sentences," but his work was soon supplanted by that of Peter Lombard. He covers a wide range of subjects, but his treatment lacks orderly arrangement, and he relies for his proofs on Scripture and reason in preference to the testimony of tradition. Taking his stand on the authority of the Bible and of papal decisions, he proceeds to enter on speculative discussion. The first book treats of God and His attributes; the second, of the creation, of angels, of the soul, of the fall of man and of original sin; the third, of the ancient and the new law, and of the Incarnation; the fourth, of God's power, of Christ's Passion and of hell and purgatory; the fifth, of the Resurrection, the descent of the Holy Ghost, the preaching of the Gospel, of the sacraments of baptism, confirmation and confession and some virtues and vices. The sixth book deals with a variety of subjects, including ignorance, negligence and frailty, good and bad spirits, the choirs of angels, merits, and the administration of the Sacrament of Penance; the seventh discusses the forgiveness of sins, penance and fasting, prayer, tithes, the civil power, the priesthood, its privileges and obligations, continency, the contemplative and active life, and matrimony. The eighth book deals with the Blessed Sacrament, the Second Advent, Antichrist, the Last Judgment and the ultimate state of the saved and the lost.
The titles of some other works which remain unpublished are given by Pitts: "In Apocalypsim Sancti Johannis"; "Super aliquot psalmos"; "De contemptu mundi"; "Super doctorum dictis"; "Praelectiones"; "Sermones." A manuscript copy of the sermons is preserved at Lambeth Palace, and Rashdall (Dictionary of Nat. Biogr.) observes of them that "the sermons, which breathe a very ascetic spirit, were evidently delivered to scholars." Chevalier is certainly in error in identifying him with the Cardinal Robert who was cardinal priest of St. Eusebius in December, 1134. This Robert was created cardinal by Innocent II in 1130, a date inconsistent with the known facts of Pullen's life.
- Surname also rendered as Polenius, Pullan, Pullein, Pullenus, Pully, and La Poule.
- Bellenger, Dominic Aidan; Fletcher, Stella (2001). Princes of the Church: A History of the English Cardinals. Stroud, UK: Sutton. p. 173. ISBN 0-7509-2630-9.
- Luscombe, David. "Robert Pullen". Oxford Dictionary of National Biography. Retrieved 21 August 2009.
- Reprinted in Patrologia Latina, with the commentary prefixed to it by the Maurist, Dom Hugo Mathoud, originally written for his edition, published at Paris in 1655.
- This article incorporates text from a publication now in the public domain: Herbermann, Charles, ed. (1913). "Robert Pullen". Catholic Encyclopedia. Robert Appleton Company.