Saint Catherine of Siena, T.O.S.D, (25 March 1347 in Siena – 29 April 1380 in Rome) was a tertiary of the Dominican Order, and a Scholastic philosopher and theologian. She also worked to bring the papacy of Gregory XI back to Rome from its displacement in France, and to establish peace among the Italian city-states. She was proclaimed a Doctor of the Church in 1970. She is one of the two patron saints of Italy, together with St. Francis of Assisi.

Caterina Benincasa was born in Siena, Italy, to Giacomo di Benincasa, a cloth dyer who ran his enterprise with the help of his sons, and Lapa Piagenti, possibly the daughter of a local poet. The house where Catherine grew up is still in existence. Born in 1347, she arrived when the black death struck the area; Siena was badly ravaged. Lapa was about forty years old when she prematurely gave birth to twin daughters, Catherine and Giovanna. Lapa had already had 22 children, but half of them had died. Giovanna was handed over to a wet-nurse, and presently died, whereas Catherine was nursed by her mother, and developed into a healthy child. She was two years old when Lapa had her 25th child, another daughter named Giovanna. Catherine had her first vision of Christ when she was age five or six, saying that Jesus smiled at her, blessed her, and left her in ecstasy. At age seven she vowed chastity.

Siena (Italian pronunciation: [ˈsjɛːna] ( listen); in English also spelled Sienna, the historic exonym) is a city in Tuscany, Italy. It is the capital of the province of Siena.

The historic centre of Siena has been declared by UNESCO a World Heritage Site. It is one of the nation's most visited tourist attractions, with over 163,000 international arrivals in 2008. Siena is famous for its cuisine, art, museums, medieval cityscape and the Palio, a horse race held twice a year.

Siena, like other Tuscan hill towns, was first settled in the time of the Etruscans (c. 900–400 BC) when it was inhabited by a tribe called the Saina. The Etruscans were an advanced people who changed the face of central Italy through their use of irrigation to reclaim previously unfarmable land, and their custom of building their settlements in well-defended hill-forts. A Roman town called Saena Julia was founded at the site in the time of the Emperor Augustus. The first document mentioning it dates from AD 70. Some archaeologists assert that Siena was controlled for a period by a Gaulish tribe called the Saenones.

St Catherine's College, often called Catz, is one of the constituent colleges of the University of Oxford in England. Its motto is Nova et Vetera ("the new and the old"). As of 2006, the college had an estimated financial endowment of £53m.

St Catherine's College was founded by the distinguished historian Alan Bullock, who went on to become the first Master of the College, and later Vice-Chancellor of Oxford University.

The College traces its descent from the Delegacy of Non-Collegiate Students, founded in 1868 to offer university education at Oxford without the costs of college membership. Nonetheless, the social role of a college was re-established by the Delegacy's students, meeting as St Catherine's Club (originally St Catharine's Club), which was named after its meeting place in a hall on Catte Street. The Club was officially recognised by the University in 1931 as St Catherine's Society. It was thus developing the characteristics of a college, and in 1956 the Delegates decided to formalise this change in status.