Question: What country was the queen for whom Robert Keate served as Serjeant-Surgeon also Empress of?

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The Queen and I (film): The Queen and I (Swedish: "Drottningen och jag" ) is a 2008 Swedish-made documentary feature film about Farah Pahlavi, the former Queen and Empress of Iran.  The film was produced and directed by Iranian-Swedish filmmaker Nahid Persson Sarvestani.  The film follows the former queen and empress and the director, a former communist, as they share ideas and concerns about the country they were both forced to leave after the revolution.

Empress, Alberta: Empress is a village located along the Alberta/Saskatchewan border; in southern Alberta 121 km north of Medicine Hat.  The town was named, in 1913, for Queen Victoria, who was also Empress of India.  In the past it was known as the "Hub of the West", connecting major cities together by the Canadian Pacific Railway.

Zhangsun Wuji: Zhangsun Wuji (died 659), courtesy name Fuji, formally the Duke of Zhao (趙公 ), was a Chinese official who served as a chancellor in the early Tang dynasty.  He was Empress Zhangsun's brother, which made him a brother-in-law of Emperor Taizong (Li Shimin) and a maternal uncle of Emperor Gaozong (Li Zhi).  He was an important advisor to Li Shimin when the latter was still the Prince of Qin during the reign of his father, Emperor Gaozu.  He helped Li Shimin overcome his brothers Li Jiancheng (the Crown Prince) and Li Yuanji (the Prince of Qi) in a succession struggle at the Xuanwu Gate Incident, eventually enabling Li Shimin to become the heir apparent and later the emperor.  He was also instrumental in Emperor Taizong's selection of Li Zhi as the Crown Prince, and was exceedingly powerful after Li Zhi took the throne as Emperor Gaozong.  However, he gradually fell out of his nephew's favour by failing to support Emperor Gaozong's decision to depose his first wife, Empress Wang, and replacing her with Empress Wu.  In 659, Zhangsun Wuji was falsely accused of treason by Empress Wu's political ally, Xu Jingzong, and eventually ordered to be sent into exile by Emperor Gaozong.  Xu Jingzong subsequently sent the official Yuan Gongyu (袁公瑜) to force Zhangsun Wuji to commit suicide on his way to exile.

Queen dowager: A queen dowager, dowager queen or queen mother (compare: princess dowager, dowager princess or princess mother) is a title or status generally held by the widow of a king.  In the case of the widow of an emperor, the title of empress dowager is used.  Its full meaning is clear from the two words from which it is composed: queen indicates someone who served as queen consort (i.e. wife of a king), while dowager indicates a woman who holds the title from her deceased husband (a queen who rules in her own right and not due to marriage to a king is a queen regnant).

Deng Sui: Deng Sui (鄧綏) (AD 81–121), formally Empress Hexi (和熹皇后, literally "the moderate and pacifying empress") was an empress during the Han dynasty of Chinese history.  She was Emperor He's second wife.  She later, as empress dowager, served as regent for his son Emperor Shang and nephew Emperor An, and was regarded as an able and diligent administrator.  She was perhaps the last effective ruler of the Eastern Han Dynasty, as the subsequent emperors and empresses dowager were largely incompetent rulers.  During her regency, there were natural disasters and wars with Xiongnu and Qiang, but she was able to remedy the disasters and largely quell the wars.  She was also praised for her attention to criminal justice.

Robert Keate: Robert Keate FRCS (14 March 1777 – 2 October 1857) was a noted British surgeon, and Serjeant-Surgeon to King William IV and Queen Victoria.

Queen Victoria: Victoria (Alexandrina Victoria; 24 May 1819 – 22 January 1901) was Queen of the United Kingdom of Great Britain and Ireland from 20 June 1837 until her death.  From 1 May 1876, she adopted the additional title of Empress of India.

Elisabeth Christine of Brunswick-Wolfenbüttel: Elisabeth Christine of Brunswick-Wolfenbüttel (28 August 1691 – 21 December 1750) was Princess of Brunswick-Wolfenbüttel, Holy Roman Empress, German Queen, Queen of Bohemia and Hungary; and Archduchess of Austria by her marriage to Emperor Charles VI.  She was renowned for her delicate beauty and also for being the mother of Empress Maria Theresa.  She was the longest serving Holy Roman Empress.

List of consorts of rulers of China: The following is a list of consorts of rulers of China.  This is a list of the consorts of Chinese monarchs.  China has periodically parted in kingdoms as well as united in empires, and there has been consorts with the title Queen as well as Empress.  The title Empress could also be given posthumously.  Note that this is a list for the main consort of the monarch and holder of the title Empress or Queen.

Rout of Winchester: In the Rout of Winchester (14 September 1141) the army of imprisoned King Stephen of England, led by his wife, Queen Matilda of Boulogne, Stephen's brother Bishop Henry of Blois, and William of Ypres, faced the army of Stephen's cousin Empress Matilda, whose forces were commanded by her half-brother Earl Robert of Gloucester.  After Empress Matilda's army besieged a castle on the edge of Winchester, Queen Matilda's army arrived and blockaded the Angevin army within the city.  Cut off from supplies, the Angevin army gave up the siege, then was crushed as it began to retreat.  Robert of Gloucester was captured and was subsequently exchanged for Stephen, who was returned to the throne of England.  However, the civil war known as The Anarchy dragged on with neither side gaining an advantage.

Supporting paragraphs: Robert Keate Queen Victoria
Answer: India