Map of Brobdingnag (Hermann Moll, before 1726)
Brobdingnag is a fictional land in Jonathan Swift's satirical novel Gulliver's Travels occupied by giants. Lemuel Gulliver visits the land after the ship on which he is travelling is blown off course and he is separated from a party exploring the unknown land.
The adjective Brobdingnagian has come to describe anything of colossal size.
The map printed as part of Part II of Gulliver's Travels appears to indicate that Brobdingnag is located on the northwest coast of California. In the book Gulliver describes how the ship reached a latitude of five degrees south, northward of Madagascar before it is blown by strong winds "a little to the east of the Molucca Islands, and about three degrees northwards of the line [equator]". From there the ship is driven by a storm "about five hundred leagues to the east" (this would place the ship still in Micronesia). Lemuel Gulliver claims to have discovered the land in 1703.
Brobdingnag is claimed to be a continent-sized peninsula six thousand miles long and three thousand miles wide, which based on the latitude and longitude given by Gulliver just before he shipwrecks there, would suggests it covers all of Alaska, the Yukon, the Bering Sea, and a small section of eastern Siberia. Further, it is claimed that a range of volcanoes up to 30 miles (48 km) high separates the country from unknown land to the northeast, and the people have never been able to develop ocean-going ships. Lorbrulgrud is claimed to be the capital with the king having a seaside palace at Flanflasnic.
Swift was highly skeptical about the reliability of travel writings and the unlikely geographic descriptions parody many unreliable travel books published at the time which Percy Adams describes as "travel lies". The drawings in Gulliver's travels are clearly based on cartographer Herman Moll's New Correct Map of the Whole World.
Flora and fauna 
The people of Brobdingnag are described as giants who are as tall as a church steeple and whose stride is ten yards. All of the other animals and plants, and even natural features such as rivers and even hail, are in proportion. The rats are the size of large dogs and the flies are the size of birds, for example. This also means that the country is far more dangerous for people of normal human size, as evidenced by Gulliver using his hanger far more often here—namely, on attacking vermin—than in any other of the strange countries he visited; fortunately for Gulliver, the people are civilized. A splacknuck is an animal about 6 feet (1.8 m) long, to which Gulliver is compared in size, although it is never explained which animal it corresponds to (probably a rodent of some sort, such as a rat). Fossil records are claimed to show that the ancestors of the Brobdingnagians were once even larger. The King of Brobdingnag argues that the race has deteriorated.
History and government 
Gulliver relates that, in the past, there were battles between the monarchy, nobility, and people resulting in a number of civil wars ending in a treaty. The monarchy is based on reason. The King of Brobdingnag finds European institutions and behaviour wanting in comparison with his country's. Based on Gulliver's descriptions of their behaviour, the King describes Europeans as "the most pernicious race of little odious vermin that nature ever suffered to crawl upon the surface of the earth."  Swift intended the moral relationship between Europeans and Brobdingnagians to be as disproportionate as the physical relationship. The King of Brobdingnag is considered to be based on Sir William Steele, a statesman and writer, whom Swift worked for early in his career.
The army of Brobdingnag is claimed to be large with 207,000 troops including 32,000 cavalry although the society has no known enemies. The local nobility commands the forces; firearms and gunpowder are unknown to them. The King scolds Gulliver when he tries to interest the statesman in the use of gunpowder.
The laws of Brobdingnag are simple and easy to follow. There is little civil litigation. Murderers are beheaded.
Note also that in Gulliver's in-character preface to the story, headed A letter from Captain Gulliver to his cousin Sympson, he specifies that the correct spelling is in fact "... Brobdingrag (for so the word should have been spelt, and not erroneously Brobdingnag), ..." (emphasis added). This "correction" by the supposed author is of course only a device used to add an element of verisimilitude to Swift's fiction.
Brobdingnagian culture consists of history, poetry, mathematics and ethics, mathematics being a particular strength. Printing has been long known but libraries are relatively small. The king has the largest library, which contains about one thousand volumes. The Brobdingnagians favour a clear literary style.
See also 
- Page, Michael; Ingpen, Robert (1987). Encyclopedia of Things That Never Were: Creatures, Places, and People. New York: Viking Press. p. 96. ISBN 0-670-81607-8. Retrieved 2011-11-01.
- Percy Adams cited in Concise Dictionary of British Literary Biography Volume 2
- Gulliver's Travels Part 2
- A voyage to Brobdingnag
- Gulliver's Travels Part II: A Voyage to Brobdingnag
- Imaginary countries: Brobdingnag
- "Jonathan Swift." Concise Dictionary of British Literary Biography, Volume 2: Writers of the Restoration and Eighteenth Century, 1660-1789. Gale Research, 1992. Reproduced in Biography Resource Center. Farmington Hills, Michigan: Thomson Gale. 2005.
- Manguel, Alberto; and Gianni Guadalupi. "Brobdingnag", The Dictionary of Imaginary Places, Harcourt Brace, New York, 2000. ISBN 0-15-100541-9
- Used as a punchline in the episode "The Hot Troll Deviation" of The Big Bang Theory