1155 (The People's Chronology)
Rome's Arnold of Brescia is interdicted by the new English pope Adrian IV and forced to flee. Betrayed by the Holy Roman Emperor Friedrich Barbarossa, he is strangled and burned at Rome; his ashes are thrown into the Tiber to prevent any of his followers from using his corpse to start a cult.
Pope Adrian IV gives Ireland to England's Henry II, but Irish kings will resist English rule (see 1166; 1170).
Henry II abolishes English fiscal earldoms and restores the royal demesne.
The half brothers of Norway's Inge I Haraldsson conspire to overthrow him (see 1142). Inge's supporters will kill both of the half brothers in the next 2 years, but Sigurd II Slembi's illegitimate son Haakon gains support from the freeholders against the higher nobility who provide Inge with his support (see 1161).
China's Song (Sung) dynasty prime minister Qin Gui (Ch'in Kuei) dies at Hangchow at age 65 (approximate), having led the opposition to continued prosecution of the war to regain northern territory that has been taken by Nüzhen (Juchen) tribesmen.
The Japanese emperor Konoe dies after a 14-year reign and is succeeded by his brother, who takes the name Goshirakawa. The new emperor has been selected by the head of the Fujiwara family, whose members have controlled the imperial court since 857 but have proved ineffective. The former emperor Sutoku, now 36, had expected the succession to go to his son and is enraged (see 1156).
Physica (Liber simplicis medicinae, or Book of Simple Medicine) by Hildegard von Bingen lists nearly 300 medicinal herbs, explaining when to pick them and how to use them (year approximate). Causae et curae (Liber compositae medicinae, or Book of Medicine Carefully Arranged) by Hildegard catalogues 47 diseases, noting that women tend to miscarry or produce defective infants if they conceive before age 20 or after age 50. She advises a pregnant woman to hold a jasper (a piece of quartz) in her hand throughout her 9-month term and during the birth because "the tongue of the ancient serpent extends itself to the sweat of the infant emerging from that mother's womb, and he lies in wait for both mother and infant at the time."
The Carmelite order of mendicant monks is founded by the crusader Berthold from Calabria and 10 companions, who establish themselves as hermits on Mount Carmel in the kingdom of Jerusalem. The monks will wear distinctive brown-and-white striped cloaks, supposedly inspired by the prophet Elijah, who was said to have disappeared into the sky on a chariot of fire, leaving behind only a cloak singed with brown stripes (see 1295).