1. Cixi: From Concubine to Regent. Born into the Manchu family, at sixteen she was brought to the Forbidden City to join Emperor Xianfeng's harem, a great honour. Her singing brought her the attention of the Emperor whereupon he became infatuated by her and she was soon visiting his chamber on a regular basis. She bore him sons--his only male heirs.
Xianfeng died in 1861 and Cixi's oldest son became the emperor Tongzhi, making her the "empress dowager" and a regent ruler. Cixi relinquished the regency when her son turned 17, but Tongzhi died two years later and Cixi became a regent again, this time for her three-year-old nephew Guangxu.
2. Anne Boleyn: After seeing how her sister had been treated by Henry VIII (pregnant and abandoned) she insisted on marriage when the King's eye fell upon her. Henry courted her for six years and caused the most important schism in the Church as he tore England from Rome and founded the Church of England.
3. Elanor of Aquitaine: Born and raised in the birthplace of courtly love, Elanor married first Louis VII of France (annulled, how shocking!) and then Henry II of England. However, her marriage to him was tempestuous and she revolted against Henry and encouraged her sons to do the same. This brought about her imprisonment for sixteen years. However, after Henry's death she ruled England for most of Richard I's reign while he went crusading.
4. Jeanne-Antoinette Poisson, Marquise de Pompadour: Louis XV of France became infatuated with the young, beautiful and married Jeanne-Antoinette and stole her away from her husband, making her a marquise and installing her at Versailles. She had not a small influence on political matters at court, taking part in the negotiations which helped to improve relations between France and Austria.
5. Georgiana Cavendish, Duchess of Devonshire: Subject of a recent film, Georgiana helped campaign for the Whig party and notoriously was supposed to have sold kisses for votes. However luminous Ms Knightley is, it's fairly obvious that Georgiana wasn't a size zero!
5. Joan of Arc: Hardly more than a child, and born into a peasant family, Joan became a French heroine by leading the army of Charles VII against the English and raising their siege of Orleans. Captured by the Burgundians, abandoned by her Dauphin and ransomed by the English, she was put on trial on charges of witchcraft and fraud. She eventually was convicted only of wearing male clothes, an offense against the Church, and was burned at the stake.
6. Catherine de Medici: She married the Duke of Orleans who became Henri II of France. She brought her Italian influence to the French court, such as music, theatre and food. She acted as regent after Henri's death, actively embroiling herself in court intrigues and attempting to strengthen France's power.
7. Melisende: Melisende married Fulk of Anjou and ruled Jerusalem at his side until his death, after which she ruled as Regent for her 13 year-old-son, who eventually rebelled against her and the kingdom was divided between them.
8. Philippa of Hainault: She invented the clothing and coal industries, faced down 12,000 Scots and rallied the troops when her husband was away...
She interceded with her husband (Edward III of England) and persuaded him to spare the lives of the Burghers of Calais who he had planned to execute as an example to the townspeople following his successful siege. She acted as a regent on several occasions when he was on the continent.
9. Catherine the Great: She married Grand Duke Peter, but the marriage was unsuccessful. After her husband became Tzar a bloodless coup deposed him and put her on the throne instead.
10. Margaret of Scandinavia: United three countries in 1387 and ruled them as a union. Worked on tax reform, monetary reform and even after her great-nephew was old enough to rule, they worked as a team, not as rivals.
11. Isabella I of Castile, Queen of Spain: When Isabella married Ferdinand of Aragon in 1469, both she and her husband became joint rulers of the whole of Spain. They governed independently, however, and Isabella initiated a program of reform which reduced the power of her rebellious nobles, streamlined her government, and encouraged scholarship. Intensely religious, she helped establish the Inquisition in Andalusia, which led to the expulsion from Spain of over 170,000 Jews. With Ferdinand, she conquered Granada, the remaining territory of the Moors. Eventually, they too were expelled from Spain.
12. Zoe Palaiologina, second wife of Ivan III of Russia: She was married to the Russian ruler to unite the Russian Orthodox and Catholic churches. Over the years, Sophia started to have great influence in her husband's decision making. It is thought that she was the first to introduce the Kremlin to grand Byzantine ceremonies and meticulous court etiquette.
13. Sophia of Russia: Peter the Great's sister ruled as regent while he and his brother were boys, and then just came out and claimed the throne. Did a damned good job, too. Lowered taxes, improved fire prevention, raised literacy, reorganized the army, granted a number of women's rights.