A grand duchy is a country or territory whose official head of state or ruler is a monarch bearing the title of grand duke or grand duchess.
 Relatively rare until the abolition of the Holy Roman Empire in 1806, the term was often used in the official name of countries smaller than most continental kingdoms of modern Europe (e.g., Denmark, Spain, United Kingdom) yet larger than most of the sovereign duchies in the Holy Roman Empire, Italy or Scandinavia (e.g. Anhalt, Lorraine, Modena, Schleswig-Holstein).
 During the 19th century there were as many as 14 grand duchies in Europe at once (a few of which were first created as exclaves of the Napoleonic empire but later re-created, usually with different borders, under another dynasty).
 Some of these were sovereign and nominally independent (Baden, Hesse and by Rhine, Mecklenburg-Schwerin, Mecklenburg-Strelitz, Oldenburg, Saxe-Weimar and Tuscany), some sovereign but held in personal union with larger realms by a monarch whose grand-dukedom was borne as a subsidiary title (Finland, Luxembourg, Transylvania), some of which were client states of a more powerful realm (Cleves and Berg), and some whose territorial boundaries were nominal and the position purely titular (Frankfurt).
The Convention of Moss was a cease fire agreement, signed on 14 August 1814 between the Swedish King and the Norwegian government.
 It followed the Swedish-Norwegian War due to Norway's claim to sovereignty.
 It also became the "de facto" peace agreement and formed the basis for the personal union between Sweden and Norway that was established when the Norwegian Storting (Parliament) elected Charles XIII of Sweden as king of Norway on 4 November 1814.
 The Union lasted until Norway declared its dissolution in 1905.
The Kalmar Union was the personal union of the kingdoms of Denmark, Norway and Sweden during the 15th century.
 The first king of the Kalmar Union was Eric of Pomerania.
 His seal combined the coats of arms of Norway (center, as an inescutcheon upon a cross over all), Denmark (in dexter chief), Sweden (the Folkung lion, in dexter base) and Pomerania (a griffin, in sinister base), and in addition the Three Crowns symbol in sinister chief; the latter heraldic design predates the Kalmar Union, and is now mostly associated with the coat of arms of Sweden, but which during the 15th century came to represent the three kingdoms of the union.
Anglo-Saxon England was early medieval England, existing from the 5th to the 11th century from the end of Roman Britain until the Norman conquest in 1066.
 It consisted of various Anglo-Saxon kingdoms until 927 when it was united as the Kingdom of England by King Æthelstan (r. 927–939).
 It became part of the North Sea Empire of Cnut the Great, a personal union between England, Denmark and Norway in the 11th century.
The Norwegian Code (Norwegian: "Norske Lov" , abbreviated NL) is the oldest part of the Norwegian law still in force, partially in force in Norway, Iceland, and the Faroe Islands.
 It was given by Christian V of (Denmark and) Norway on 15 April 1687 and entered into force on 29 September 1688, as the legal code for the Kingdom of Norway including its dependencies (the Faroe Islands, Iceland, and Greenland).
 Norway was a nominally sovereign kingdom, but politically (although not economically) the weaker part in a personal union with Denmark at the time.
 The Norwegian Code was largely based on the Danish Code ("Danske Lov", DL), promulgated in 1683 and itself mostly based on older Danish laws, but the Norwegian Code had some differences from the Danish Code in some areas, such as inheritance law, agricultural law, law relating to hunting, fisheries and trade, and military issues.
 In the 19th and 20th centuries, most of the provisions were gradually repealed as they were replaced by modern laws.
 The code as such remains in force, and it was last amended on 1 January 1993.
 As late as the postwar era, the Supreme Courts of Denmark and Norway interpreted identical provisions from the Danish and Norwegian Code respectively; they came to the opposite conclusions regarding the meaning of identical provisions NL 6-10-2 (in force in Norway until 1985) and DL 6-10-2 (still in force in Denmark).
 The provision is ambiguously worded and regulates compensation for damage caused by livestock and dogs.
 The Supreme Court of Norway ruled on the meaning of this provision in 1954.
Norges Skaal (English: Norway’s Toast ), was first written in 1771 by Johan Nordahl Brun in Copenhagen during the period when Norway was in a personal union with Denmark as a drinking song for the Norwegian literary society in Copenhagen.
1814 was a pivotal year in the history of the Kingdom of Norway.
 It started with Norway in a union with Denmark, subject to a naval blockade by The British Empire, being ceded to the King of Sweden.
 In May a constitutional convention declared Norway independent.
 By the end of the year the Norwegian parliament had agreed to join with Sweden in a personal union under the monarch of Sweden.
 Although nationalist aspirations were not to be fully realized until the events of 1905, 1814 was the crisis and turning point in events that would lead to a fully independent Norway.
The Kalmar Union or Union of Kalmaris (Danish, Norwegian and Swedish: "Kalmarunionen" ; Latin: "Unio Calmariensis" ) was a personal union that from 1397 to 1523 joined under a single monarch the three kingdoms of Denmark, Sweden (then including parts of Finland), and Norway, together with Norway's overseas dependencies (then including Iceland, Greenland, the Faroe Islands and the Northern Isles).
 The Union was not quite continuous; there were several short interruptions.
 Legally the countries remained separate sovereign states, but with their domestic and foreign policies being directed by a common monarch.
The Danish North Sea Empire, also known as the Anglo-Scandinavian Empire, was the thassalocratic domain ruled by Cnut the Great as king of England, Denmark, Norway and parts of what is now Sweden between 1016 and 1035.
 As one historian put it:
There have been 12 monarchs of the Kingdom of Great Britain and the United Kingdom (see Monarchy of the United Kingdom) since the merger of the Kingdom of England and the Kingdom of Scotland on 1 May 1707.
 England and Scotland had been in personal union under the House of Stuart since 24 March 1603.
 On 1 January 1801, Great Britain merged with the Kingdom of Ireland (also previously in personal union with Great Britain) to form the United Kingdom of Great Britain and Ireland.
 After most of Ireland left the union on 6 December 1922, its name was amended on 12 April 1927 to the United Kingdom of Great Britain and Northern Ireland.

Question: What personal union between England, Denmark and Norway was also known as the Anglo-Scandinavian Empire?
Answer: North Sea Empire