Justus (occasionally Iustus; died on 10 November between 627 and 631) was the fourth Archbishop of Canterbury. He was sent from Italy to England by Pope Gregory the Great, on a mission to Christianize the Anglo-Saxons from their native paganism, probably arriving with the second group of missionaries despatched in 601. Justus became the first Bishop of Rochester in 604, and attended a church council in Paris in 614.

Following the death of King Æthelberht of Kent in 616, Justus was forced to flee to Gaul, but was reinstated in his diocese the following year. In 624 Justus became Archbishop of Canterbury, overseeing the despatch of missionaries to Northumbria. After his death he was revered as a saint, and had a shrine in St Augustine's Abbey, Canterbury.

Justus was an Italian and a member of the Gregorian mission sent to England by Pope Gregory I. Almost everything known about Justus and his career is derived from the early 8th-century Historia ecclesiastica gentis Anglorum of Bede. As Bede does not describe Justus' origins, nothing is known about him prior to his arrival in England. He probably arrived in England with the second group of missionaries, sent at the request of Augustine of Canterbury in 601. Some modern writers describe Justus as one of the original missionaries who arrived with Augustine in 597, but Bede believed that Justus came in the second group. The second group included Mellitus, who later became Bishop of London and Archbishop of Canterbury.

Justus Freiherr von Liebig (12 May 1803 – 18 April 1873) was a German chemist who made major contributions to agricultural and biological chemistry, and worked on the organization of organic chemistry. As a professor, he devised the modern laboratory-oriented teaching method, and for such innovations, he is regarded as one of the greatest chemistry teachers of all time. He is known as the "father of the fertilizer industry" for his discovery of nitrogen as an essential plant nutrient, and his formulation of the Law of the Minimum which described the effect of individual nutrients on crops. He also developed a manufacturing process for beef extracts, and founded a company, Liebig Extract of Meat Company, that later trademarked the Oxo brand beef bouillon cube.

Liebig was born in Darmstadt into a middle class family. From childhood he was fascinated by chemistry. At the age of 13, Liebig lived through the year without a summer, when the majority of food-crops in the northern hemisphere were destroyed by a volcanic winter. Germany was among the hardest-hit in the global famine that ensued, and the experience is said to have shaped Liebig's later work. Thanks in part to Liebig's innovations in fertilizers and agriculture, the 1816 famine became known as "the last great subsistence crisis in the Western world".