John Caius (born John Kays ; 6 October 1510 – 29 July 1573), also known as Johannes Caius and Ioannes Caius, was an English
physician
A physician, medical practitioner (British English), medical doctor, or simply doctor is a health professional who practices medicine, which is concerned with promoting, maintaining or restoring health through the Medical education, study, Med ...
, and second founder of
Gonville and Caius College, Cambridge
Gonville and Caius College, commonly known as Caius ( ), is a constituent college of the University of Cambridge in Cambridge, England. Founded in 1348 by Edmund Gonville, it is the fourth-oldest of the University of Cambridge's 31 colleges and ...
. Scholar and physician to
Edward VI
Edward VI (12 October 1537 – 6 July 1553) was King of England and King of Ireland, Ireland from 28 January 1547 until his death in 1553. He was crowned on 20 February 1547 at the age of nine. The only surviving son of Henry VIII by his thi ...
and
Mary I of England
Mary I (18 February 1516 – 17 November 1558), also known as Mary Tudor, was Queen of England and Ireland from July 1553 and Queen of Spain as the wife of King Philip II from January 1556 until her death in 1558. She made vigorous ...
.
Biography
Early years
Caius was born in
Norwich
Norwich () is a cathedral city and district of the county of Norfolk, England, of which it is the county town. It lies by the River Wensum, about north-east of London, north of Ipswich and east of Peterborough. The population of the Norwich ...
and was educated at
Norwich School
Norwich School (formally King Edward VI Grammar School, Norwich) is a private selective day school in the close of Norwich Cathedral, Norwich. Among the oldest schools in the United Kingdom, it has a traceable history to 1096 as an episcop ...
. In 1529, he was admitted as a student at
Gonville Hall, Cambridge, founded by
Edmund Gonville
Edmund Gonville (died 1351) was an English priest who founded Gonville Hall at the University of Cambridge in 1348, which later was re-founded by John Caius to become Gonville and Caius College, Cambridge. Gonville Hall was his third foundation. ...
in 1348, where he seems to have mainly studied
divinity
Divinity (from Latin ) refers to the quality, presence, or nature of that which is divine—a term that, before the rise of monotheism, evoked a broad and dynamic field of sacred power. In the ancient world, divinity was not limited to a single ...
.
After graduating in 1533, he visited Italy, where he studied under
Montanus
Montanus (; Greek: Μοντανός) was the second century founder of Montanism and a self-proclaimed prophet. Montanus emphasized the work of the Holy Spirit, in a manner which set him apart from the Great Church.
Life
Little is known about t ...
and
Vesalius
Andries van Wezel (31 December 1514 – 15 October 1564), Latinization of names, latinized as Andreas Vesalius (), was an anatomist and physician who wrote ''De humani corporis fabrica, De Humani Corporis Fabrica Libri Septem'' (''On the fabric ...
at
Padua
Padua ( ) is a city and ''comune'' (municipality) in Veneto, northern Italy, and the capital of the province of Padua. The city lies on the banks of the river Bacchiglione, west of Venice and southeast of Vicenza, and has a population of 20 ...
. In 1541 he took his degree as a physician at the
University of Padua
The University of Padua (, UNIPD) is an Italian public research university in Padua, Italy. It was founded in 1222 by a group of students and teachers from the University of Bologna, who previously settled in Vicenza; thus, it is the second-oldest ...
.
In 1543 he visited several parts of Italy, Germany and France and then returned to England. Upon his return from Italy he Latinised his surname which was somewhat fashionable at the time.
Career

Caius was a physician in London in 1547, and was admitted as a fellow of the
College of Physicians
A college (Latin: ''collegium'') may be a tertiary educational institution (sometimes awarding degrees), part of a collegiate university, an institution offering vocational education, a further education institution, or a secondary school ...
, of which he was for many years president.
In 1551 he was attending in
Shrewsbury
Shrewsbury ( , ) is a market town and civil parish in Shropshire (district), Shropshire, England. It is sited on the River Severn, northwest of Wolverhampton, west of Telford, southeast of Wrexham and north of Hereford. At the 2021 United ...
when a notable outbreak of
sweating sickness
Sweating sickness, also known as the sweats, English sweating sickness, English sweat or ''sudor anglicus'' in Latin, was a mysterious and contagious disease that struck England and later continental Europe in a series of epidemics beginning i ...
occurred in the town; the following year, after his return to London, he published ''A Boke or Counseill Against the Disease Commonly Called the Sweate, or Sweatyng Sicknesse'' (1552), which became the main source of knowledge of this disease, now understood to be
influenza
Influenza, commonly known as the flu, is an infectious disease caused by influenza viruses. Symptoms range from mild to severe and often include fever, runny nose, sore throat, muscle pain, headache, coughing, and fatigue. These sympto ...
.
In 1557 Caius, at that time physician to
Queen Mary, enlarged the foundation of his old college, changed the name from "Gonville Hall" to "Gonville and Caius College", and endowed it with several considerable estates, adding an entire new court at the expense of £1,834 (). He accepted the mastership of the college 24 January 1559 on the death of
Thomas Bacon, and held it until about a month before his own death.
He was physician to
Edward VI
Edward VI (12 October 1537 – 6 July 1553) was King of England and King of Ireland, Ireland from 28 January 1547 until his death in 1553. He was crowned on 20 February 1547 at the age of nine. The only surviving son of Henry VIII by his thi ...
,
Queen Mary and
Queen Elizabeth Queen Elizabeth, Queen Elisabeth or Elizabeth the Queen may refer to:
Queens regnant
* Elizabeth I (1533–1603; ), Queen of England and Ireland
* Elizabeth II (1926–2022; ), Queen of the United Kingdom and other Commonwealth realms
* Queen B ...
.
From this position he was dismissed in 1568 on account of his adherence to the
Roman Catholic
The Catholic Church (), also known as the Roman Catholic Church, is the largest Christian church, with 1.27 to 1.41 billion baptized Catholics worldwide as of 2025. It is among the world's oldest and largest international institut ...
faith. He was incongruously accused both of
atheism
Atheism, in the broadest sense, is an absence of belief in the Existence of God, existence of Deity, deities. Less broadly, atheism is a rejection of the belief that any deities exist. In an even narrower sense, atheism is specifically the ...
, and of keeping secretly a collection of ornaments and
vestment
Vestments are Liturgy, liturgical garments and articles associated primarily with the Christianity, Christian religion, especially by Eastern Christianity, Eastern Churches, Catholic Church, Catholics (of all rites), Lutherans, and Anglicans. ...
s for Roman Catholic use. The latter were found and burned in the college court.
He was elected nine times president of the College of Physicians, an account of which, ''Annales collegii medicorum 1520-1565'', he left in manuscript.
He returned to Cambridge from London for a few days in June 1573, about a month before his death, and resigned the mastership to
Thomas Legge
Thomas Legge (; 1535 – 12 July 1607) was an English educator and playwright, prominently known for his play ''Richardus Tertius'', which is considered to be the first history play written in England.
Early life and education
Legge was the se ...
, a tutor at
Jesus College. He died at his London house, in
St Bartholomew's Hospital
St Bartholomew's Hospital, commonly known as Barts, is a teaching hospital located in the City of London. It was founded in 1123 by Rahere, and is currently run by Barts Health NHS Trust.
History
Early history
Barts was founded in 1123 by ...
, on 29 July 1573, but his body was brought to Cambridge, and buried in the chapel under the monument which he had designed.
The question of whether he was the inspiration for the character of Dr Caius in
Shakespeare
William Shakespeare ( 23 April 1564 – 23 April 1616) was an English playwright, poet and actor. He is widely regarded as the greatest writer in the English language and the world's pre-eminent dramatist. He is often called England's natio ...
's play the ''
Merry Wives of Windsor
''The Merry Wives of Windsor'' or ''Sir John Falstaff and the Merry Wives of Windsor'' is a comedy by William Shakespeare first published in 1602, though believed to have been written in or before 1597. The Windsor of the play's title is a ref ...
'' has been discussed at length by
Arnold McNair, 1st Baron McNair.
Legacy

Caius was a learned, active and benevolent man. In 1557 he erected a monument in
St Paul's Cathedral
St Paul's Cathedral, formally the Cathedral Church of St Paul the Apostle, is an Anglican cathedral in London, England, the seat of the Bishop of London. The cathedral serves as the mother church of the Diocese of London in the Church of Engl ...
to the memory of
Thomas Linacre
Thomas Linacre or Lynaker ( ; 20 October 1524) was an English humanist scholar, Catholic priest, and physician, after whom Linacre College, Oxford, and Linacre House, a boys' boarding house at The King's School, Canterbury, were named.
Linacre ...
. In 1564, he obtained a grant for Gonville and Caius College to take the bodies of two malefactors annually for
dissection
Dissection (from Latin ' "to cut to pieces"; also called anatomization) is the dismembering of the body of a deceased animal or plant to study its anatomical structure. Autopsy is used in pathology and forensic medicine to determine the cause of ...
; he was thus an important pioneer in advancing the science of
anatomy
Anatomy () is the branch of morphology concerned with the study of the internal structure of organisms and their parts. Anatomy is a branch of natural science that deals with the structural organization of living things. It is an old scien ...
. He probably devised, and certainly presented, the silver
caduceus
The caduceus (☤; ; , ) is the staff carried by Hermes in Greek mythology and consequently by Hermes Trismegistus in Greco-Egyptian mythology. The same staff was borne by other heralds like Iris (mythology), Iris, the messenger of Hera. The s ...
now in the possession of Caius College as part of its insignia. He first gave it to the College of Physicians, and afterwards presented the London College with another.
Works
Caius was also a pioneer naturalist, prepared to make his own observations about nature rather than simply relying on accepted authorities. He was ready to make journeys about the country to see and record unusual animals. As such he could be considered also a pioneer of
zoology
Zoology ( , ) is the scientific study of animals. Its studies include the anatomy, structure, embryology, Biological classification, classification, Ethology, habits, and distribution of all animals, both living and extinction, extinct, and ...
, not yet recognised as a separate science.
He corresponded with the Swiss naturalist
Conrad Gesner
Conrad Gessner (; ; 26 March 1516 – 13 December 1565) was a Old Swiss Confederacy, Swiss physician, natural history, naturalist, bibliographer, and philologist. Born into a poor family in Zürich, Switzerland, his father and teachers quickly ...
, with whom he had made friends while returning from Padua. He wrote a study of British dogs to send to Gesner as a contribution (not used) to Gesner's ''
Historiae animalium
("History of the Animals"), published in Zurich in 1551–1558 and 1587, is an encyclopedic "inventory of renaissance zoology" by Conrad Gessner (1516–1565). Gessner was a medical doctor and professor at the Carolinum in Zürich, the precurso ...
'', and also sent Gesner drawings of dogs, which were printed in later editions of Gesner's work.
Caius' Catholic religious convictions did not prevent his friendship with the
Protestant
Protestantism is a branch of Christianity that emphasizes Justification (theology), justification of sinners Sola fide, through faith alone, the teaching that Salvation in Christianity, salvation comes by unmerited Grace in Christianity, divin ...
Gesner (indeed, the ''Historiae Animalium'', to which Caius contributed, was under
Pope Paul IV
Pope Paul IV (; ; 28 June 1476 – 18 August 1559), born Gian Pietro Carafa, was head of the Catholic Church and ruler of the Papal States from 23 May 1555 to his death, in August 1559. While serving as papal nuncio in Spain, he developed ...
placed on the
Roman Catholic Church
The Catholic Church (), also known as the Roman Catholic Church, is the List of Christian denominations by number of members, largest Christian church, with 1.27 to 1.41 billion baptized Catholics Catholic Church by country, worldwid ...
's
list of prohibited books).
His last literary production was a
history of Cambridge University, ''Historia Cantabrigiensis Academiae'' (London, 1574).
Bibliography
*''Annals of the College from 1555 to 1572''
*Translation of several of Galen's works, printed at different times abroad.
*''Hippocrates de Medicamentis'', first discovered and published by Dr Caius; also ''De Ratsone Vicius'' (Lov. 1556, 8vo)
*''De Mendeti Methodo'' (Basel, 1554; London, 1556, Svo)
** Reprint:
*''A Boke or Counseill against the Disease Called the Sweate'', London 1552
** Reprint:
**Reprint: Caius, John, ''A Boke or Counseill against the Disease Called the Sweate'', London 1552. Facsimile ed., 1937, Scholars' Facsimiles & Reprints, .
*''De Ephemera Britannica'' (''Account of the Sweating Sickness in England'') (London, 1556, 1721)
** Reprint:
*''History of the University of Cambridge'' (London, 1568, 8vo; 1574, 4to, in Latin)
** Reprint:
*''De Thermis Britannicis''; but it is doubtful whether this work was ever printed
*''De Rariorum animalium atque stirpium historia, libellus.''(''Of Some Rare Plants and Animals'') (London, 1570)
** Reprint:
*** Digital text:
*''De Canibus Britannicis'' (1570, 1729)
** Reprint:
**''Of Englishe Dogges: The Diuersities, the Names, the Natures, and the Properties'' (London, 1576).
** Reprint:
*''De Libris suis: De Libris propriis'' (London, 1570).
** Reprint:
*''De Pronunciatione Graecae et Latinae Linguae'' (London, 1574)
** Reprint:
*** Digital text:
See also
*
Thomas Caius,
Master of University College, Oxford
The head of University College, Oxford is known as the Master.
University College was founded in Oxford, England, through a legacy from William of Durham in 1249. The names of early Masters are not known. The earliest surviving College Regist ...
(1561–1572)
*
Bloodhound
The bloodhound is a large scent hound, originally bred for hunting deer, wild boar, rabbits, and since the Middle Ages, for tracking people. Believed to be descended from hounds once kept at the Abbey of Saint-Hubert, Belgium, in French it is ...
Notes
References
Further reading
*
*
*
*
*
*
*
External links
John Caiuson th
Gonville and Caius College website*
*
*
* (this anthology lacks global pagination)
{{DEFAULTSORT:Caius, John
Academics from Norwich
People educated at Norwich School
Alumni of Gonville and Caius College, Cambridge
Fellows of Gonville and Caius College, Cambridge
Founders of Gonville and Caius College, Cambridge
Masters of Gonville and Caius College, Cambridge
History of anatomy
University of Padua alumni
16th-century English medical doctors
1510 births
1573 deaths
Presidents of the Royal College of Physicians
Medical doctors from Norwich
Founders of colleges of the University of Cambridge