Infanta Catarina of Portugal (or of Braganza) was born in Vila Viçosa as the second surviving daughter of John IV of Portugal (at the time Duke of Braganza) and his wife, Louise of Guzman (Medina-Sidonia). Through her mother, she was a 2nd great granddaughter of Saint Francis Borgia. Although she was raised in a convent, Catherine's upbringing and education were closely supervised by her mother.
Following the restoration of a Portuguese Royal House, and her father's accession to the throne on 1 December 1640, she was variously proposed as a bride for John of Austria, Francois de Vendome, duc de Beaufort, Louis XIV and Charles II. She was seen as a useful conduit for contracting an alliance between Portugal and England, after the Treaty of the Pyrenees in 1659 in which Portugal was arguably abandoned by France. Upon Charles' restoration to the English throne in 1660, Catherine's mother reopened negotiations with his counselors, and a marriage treaty was signed 23 June 1661.
She was married by proxy in Lisbon on 23 April 1662. After her arrival at Portsmouth on 14 May 1662, the couple were married in two more ceremonies – a Catholic one conducted in secret, followed by a public Anglican service – on 21 May.
Her large dowry brought the port cities of Tangier and Bombay to British control. The former had only a transitory significance, but the latter had a major lasting influence on both the development of the British Empire and the History of India, as the British would develop Bombay - with only some 10,000 inhabitants under the Portuguese - into a major center of commerce and the metropolis it is at present. It would be no exaggeration to say that, had Catherine of Braganza married one of her other suitors, the geography and economy of present-day India might have been significantly different.
Catherine introduced the custom of drinking tea in England. Although some have claimed that Queens, a borough of New York City, was named after Catherine of Braganza, her name is not mentioned in the first 200 years of historical documents that have been preserved in the county archives.