Boethius (475-524 A.D.)

The importance of Boethius (ca. 475-524) in the story of mathematics rests on the fact that his writings on geometry and arithmetic remained standard texts in the monastic schools for many centuries. These very meager works came to be considered as the height of mathematical achievement, and thus well illustrate the poverty of the subject in Christian Europe during the Dark Ages. For the Geometry consists of nothing but the statements of the propositions of Book I and a few selected propositions of Books III and IV of Euclid’s Elements, along with some applications to elementary mensuration, and the Arithmetic is founded on the tiresome and half mystical, but once highly reputed, work of Nicomachus of four centuries earlier. (It is contended by some that part, at least, of the Geometry is spurious. ) With this works, and his writings on philosophy, Boethius became the founder of medieval scholasticism. His high ideals and inflexible integrity led him into political troubles. He suffered a cruel end for which the Church declared him a martyr.

Bede the Venerable (673-735 A.D.)

Bede (ca. 673-735), later qualified as Bede the Venerable was born in Northumberland, England, and became one of the greatest of the medieval Church scholars. His numerous writings include some on mathematical subjects, chief of which are his treatises on the calendar and on finger reckoning.
 

Alcuin (735-804 A.D.)

Alcuin, born in Yorkshire, was another English scholar. He was called to France to assist Charlemagne in his ambitious educational project. Alcuin wrote on a number of mathematical topics and is doubtfully credited with a collection of puzzle problems that influenced  textbook writers for many centuries.

Gerbert (950-1003 A.D.)

Gerbert was born in Auvergne, France, and early showed unusual abilities. He was one of the first Christians to study in the Moslem schools of Spain, and there is evidence that he may have brought back the Hindu-Arabic numerals, without the zero, to Christian Europe. He is said to have constructed abaci, terrestrial and celestial globes, a clock, and perhaps an organ. Such accomplishments corroborated the suspicions of some of his contemporaries that he had traded his soul to the Devil. Nevertheless, he steadily rose in the Church and was finally elected to the papacy in 999 A.D. He was considered as a profound scholar and wrote on astrology, arithmetic and geometry.

Adelard of Bath (1120 A.D.)

One of the earliest Christian scholars to engage in the pursuit of the history of mathematics was the English monk Adelard of Bath, who seems to have visited Spain between 1126-1129 A.D. and traveled extensively through Greece, Syria, and Egypt. Adelard is credited with Latin translations of Euclid’s Elements and of al-Khowarizmi’s astronomical tables. There are thrilling allusions to the physical risks run by Adelard in his acquisition of Arabic learning; to obtain the jealously guarded knowledge, he disguised himself as a Mohammedan student.