This surname of BORGEN was a Spanish habitation name from a place in the province of Saragossa, so called from the Old Spanish word BORG, meaning a tower. The name is also spelt BORJAS, BORGE, BORGAN, BORGER and BORGHI. During the Middle Ages surnames were first used in order to distinguish between numbers of people bearing the same christian name. As taxation, under William The Conqueror, who invaded England in 1066, became the law, documentation became essential, and names were chosen from a man's trade, his father's name, some personal physical characteristic, or from his place of residence. Surnames derived from placenames are divided into two broad categories; topographic names and habitation names. Topographic names are derived from general descriptive references to someone who lived near a physical feature such as an oak tree, a hill, a stream or a church. Habitation names are derived from pre-existing names denoting towns, villages and farmsteads. Other classes of local names include those derived from the names of rivers, individual houses with signs on them, regions and whole countries. The powerful and notorious BORGIA family in Renaissance Rome, was of Spanish origin. Rodrigo Borja (1431-503) was born in Jativa, Spain, became Pope as Alexander VI. He was an able politician and administrator, but he is remembered more for his irreligious worldliness. Among his four children by his mistress Vannozza Catanei were, Cesare Borgia, (1475-1507) and Lucrezia (1480-1519). Cesare was a brilliant but unscrupulous soldier and politician, who was made a cardinal at the age of 17, and implicated in the murders of his elder brother and his sister's husband, among others. Lucrezia was rumoured to have been poisoner and to have had incestuous relations with her father and her brother, but she led a conventional life after her marriage to her third husband, Alfonso d'Este, Duke of Ferrara, in 1501, and became a patron of the arts and sciences.