Roger of Hereford facts for kids

Roger of Hereford was a very smart person from the Middle Ages. He was an astronomer, astrologer, alchemist, and mathematician. He worked in Hereford, England, around the late 1100s, from about 1178 to 1198. People also knew him as Rogerus Herefordensis, Roger Infans, or Roger Puer.

Who Was Roger of Hereford?

We don't know much about Roger's early life. We don't know where he was born, when he was born, or where he went to school. The first time we hear about him is in 1176.

Early Work and Connections

In 1176, a religious leader named Gilbert Foliot asked Roger to create a special calendar. This calendar, called a computus, helped calculate important church dates. In his work, Roger showed that some older calculations were wrong. He used ideas from Hebrew and Arabic scholars, which was quite advanced for his time.

Roger's connection to Hereford is clear because his star charts used Hereford as their main point in 1178. It's very likely that he is the same "Roger Infans" mentioned in official documents from Hereford between 1186 and 1198.

Roger's Important Writings

Roger wrote several important books. These books helped share knowledge during the Middle Ages.

Astronomy Book

One of his main books was about astronomy. It was called Liber de Quatuor Partibus Judiciorum Astronomie. In this book, Roger used ideas from other smart people like Raimond de Marseille. He also used translations of Arabic texts by Juan de Sevilla and Hermann of Carinthia.

Astrology Book

Roger also wrote a book about astrology called Judicial Astrology. Astrology was a way people tried to understand the future or a person's personality based on the positions of stars and planets. This book explained different ways to use astrology. It even had a section on how to figure out what someone was really asking when they came for an astrological reading.

A scholar named Nicholas Whyte first studied this book in detail in 1991. He thought that one of the horoscopes (a chart showing the positions of planets at a certain time) in the book might have belonged to Eleanor of Aquitaine, a very famous queen. Later, a more complete study of all 22 copies of Judicial Astrology was done by Chris Mitchell at the University of Leicester.

New Ways to Calculate

Roger might have also created a new way to calculate horoscopes. A translation by Alfred of Shareshill was even dedicated to Roger, showing his importance.

Roger's Legacy

Roger of Hereford was very important because he helped pass on knowledge from older scholars. He shared the ideas of people like Adelard of Bath and other ancient writers. Later in his life, Roger even lived with another famous scholar, Robert Grosseteste, in Hereford.