Question: What other country was the queen who launched Dannebrog, also a queen for between 1918 and 1944?

Context paragraphs:
Gwyn Avenue–Bridge Street Historic District: Gwyn Avenue–Bridge Street Historic District is a national historic district located at Elkin, Surry County, North Carolina.  The district encompasses 124 contributing buildings and 1 contributing site in a predominantly residential section of Elkin.  They were primarily built between about 1891 and 1955 and include notable examples of Queen Anne, Colonial Revival, and Bungalow / American Craftsman architecture.  Notable buildings include the Elkin Presbyterian Church (1937, 1944, 1950, 1955, 1961), First Baptist Church (1955, 1968), Alexander Martin Smith House (1893–1897) designed by George Franklin Barber, the Gwyn-Chatham-Gwyn House (c. 1872, 1911, 1936), Richard Gwyn Smith House (c. 1918), and Mason Lillard House (c. 1910).

Edgar A. Sharp: Edgar Allan Sharp (June 3, 1876 – November 27, 1948) was a United States Representative from New York.  Born in Patchogue, Suffolk County, he attended the public and high schools, engaged as a clerk in the post office at Patchogue from 1898 to 1906 and served as assistant postmaster from 1906 to 1918.  He was in charge of construction work for the Knights of Columbus in France and England from April 1918 to January 1920 and engaged in the real estate and insurance business in Patchogue and as real estate appraiser for Suffolk County from 1920 to 1944.  He was an auctioneer from 1929 to 1944 and was also interested in banking.

HDMY Dannebrog (A540): Her Danish Majesty's Yacht "Dannebrog" (A540) (Danish: "KDM Dannebrog" ) was launched by Queen Alexandrine at Copenhagen in 1931, and commissioned on 26 May 1932.  The yacht now serves as the official and private residence for Queen Margrethe II of Denmark, the Prince Consort, and members of the Royal Family when they are on official visits overseas and on summer cruises in Danish waters.  When at sea, the Royal Yacht also participates in surveillance and sea-rescue services.

Alexandrine of Mecklenburg-Schwerin: Alexandrine of Mecklenburg-Schwerin (24 December 1879 – 28 December 1952) was Queen of Denmark as the spouse of King Christian X.  She was also Queen of Iceland from 1 December 1918 to 17 June 1944.

SM UC-78: SM "UC-78" was a German Type UC II minelaying submarine or U-boat in the German Imperial Navy (German: "Kaiserliche Marine" ) during World War I.  The U-boat was ordered on 12 January 1916 and was launched on 8 December 1916.  She was commissioned into the German Imperial Navy on 10 January 1917 as SM "UC-78".  In twelve patrols "UC-78" was credited with sinking 1 warship, either by torpedo or by mines laid.  "UC-78" was rammed and sunk by the British steamer "Queen Alexandra" west of Cherbourg on 9 May 1918.

Sapphire Jubilee of Queen Elizabeth II: On 6 February 2017, the Sapphire Jubilee of Queen Elizabeth II, marking sixty-five years of her reign, occurred.  The longest-reigning monarch in British history, Queen Elizabeth II was the first British monarch to have a sapphire jubilee.  This Jubilee featured blue stamps from the Royal Mail, commemorative coins from the Royal Mint, and a reissue of an official 2014 portrait of Queen Elizabeth II by David Bailey.  In this official portrait the Queen wears sapphire jewellery which she received as a wedding present from her father.  The Jubilee also involved a gun salute at the Tower of London, a gun salute in Green Park, gun salutes in several other places around the United Kingdom, and the ringing of the bells in Westminster Abbey.  Theresa May, the Prime Minister of the United Kingdom, congratulated Queen Elizabeth II in regard to the occasion, saying in part, "I know the nation will join with me today in celebrating and giving thanks for the lifetime of service Her Majesty the Queen has given to our country and to the Commonwealth."

List of Prussian consorts: The Queen of Prussia was the queen consort of the ruler of the Kingdom of Prussia, from its establishment in 1701 to its abolition in 1918.  As all rulers of Prussia had to be male, there was never a Queen regnant of Prussia.  Until 1806, the Queen of Prussia was also Electress of Brandenburg; after 1871, she was also German Empress.  Until 1772, her title was "Queen in Prussia" (see King in Prussia).

Labotsibeni Mdluli: Labotsibeni Mdluli, also known as Gwamile (c. 1859 – December 15, 1925), was the Queen Mother and Queen Regent of Swaziland.  She was born at Luhlekweni in northern Swaziland about 1858, the daughter of Matsanjana Mdluli.  At the time of her birth, her father was away fighting the people of Tsibeni in what became the Barberton district of the Transvaal—hence her name.  Following the death of her father she moved with her uncle Mvelase Mdluli to the royal homestead at Ludzidzini in the Ezulwini Valley, central Swaziland.  It was there that she received some training in statecraft from the old queen mother, Thandzile (‘LaZidze’), widow of King Sobhuza I and mother of Mswati II.  She became one of the wives of the young Ingwenyama or king of the Swazi, Mbandzeni Dlamini (c.1857–1889), soon after his succession in 1874.  They had four surviving children, three sons, Bhunu (c.1875–1899), Malunge (c.1880–1915), and Lomvazi (c.1885–1922), and a daughter, Tongotongo (c.1879–1918).

Fruehauf Trailer Corporation: Fruehauf Trailer Corporation, previously Fruehauf Trailer Company (1918–1963) and Fruehauf Corporation (1963–1989), was an American company engaged in the manufacture and sale of truck trailers, and other machinery and equipment, with headquarters located in Detroit, Michigan.  It was founded in 1918 in Detroit, after August Fruehauf created the semi-trailer and launched a new industry.  The Fruehauf trailer company introduced revolutionary inventions to trucking and transportation with hydraulic dump trailers, bulk tanker trailers, and automatic fifth wheel coupling among their over one thousand patents, including the shipping container in 1956.  Expanding across the country, Fruehauf had 16 plants and over 80 distributorships for parts and service.  Globally, the company expanded into Europe, South America and Asia.  Following a proxy battle in the late 1980s the company filed for bankrupt protection in 1997.  International divisions became independent, U.S. subsidiaries like Kelsey Hayes, Pro-Par, Budd Wheels and Hobbs were sold; Wabash National acquired the crippled company in 1997.

ʻAnaseini Takipō: 'Anaseini Takipō Afuha'amango (1 March 1893 – 26 November 1918) was the Queen consort of Tonga from 1909 to 1918.  She was the second wife of George Tupou II.  Her name was also often rendered as Ana Seini Takipo.

Supporting paragraphs: HDMY Dannebrog (A540) Alexandrine of Mecklenburg-Schwerin
Answer: Iceland