The mythology and legends of many different cultures include mythological creatures of human appearance but prodigious size and strength. "Giant" is the English word commonly used for such beings, derived from one of the most famed example: the gigantes of Greek mythology.
In various Indo-European mythologies, gigantic peoples are featured as primeval races associated with chaos and the wild nature, and they are frequently in conflict with the gods, be they Olympian or Norse. There are also historical stories featuring giants in the Old Testament, perhaps most famously Goliath, although in such references the term may simply be used to denote a human of extremely large size and strength. They are attributed superhuman strength and physical proportions, a long lifespan, and thus a great deal of knowledge as well. Yet, they are weak in both morals and imagination.
Fairy tales such as Jack and the Beanstalk, have formed our modern perception of giants as stupid and violent monsters, frequently said to eat humans, and especially children. However, in some more recent portrayals, like those of Oscar Wilde, the giants are both intelligent and friendly.
In pseudoscience 'giants' often refers to tall extraterrestrials who visited the planet and created the human race.
The Anakites, who "come from the Nephilim" (Numbers 13:28-33), the Emites (Deuteronomy 2:10), and the Rephaites (Joshua 12:4) were giants living in the Promised Land. The Bible also records the famous strife between David and the giant Goliath, ending with the defeat of the latter. Goliath was "six cubits and a span" in height--over nine feet tall (1 Samuel 17:4 KJV).
Biblical City Where David Battled Goliath Found? - National Geographic - November 21, 2008
The remains of an ancient gate has pinpointed the location of the biblical city Sha'arayim, say archaeologists working in Israel. In the Bible, young King David is described as battling Goliath in the city, before eventually killing him in the Elah Valley.
Also, Gog and Magog are usually considered to be giants, and are also found in the folklore of Britain.
In Hinduism, the giants are called Daityas. They were a race who fought against the gods because they were jealous of their Deva half-brothers. Some Daityas from Hindu mythology include Kumbhakarna and Hiranyaksha.
In Greek mythology the gigantes were (according to the poet Hesiod) the children of Uranos and Gaea (The Heaven and the Earth). They were involved in a conflict with the Olympian gods called the Gigantomachy , which was eventually settled when the hero Heracles decided to help the Olympians. The Greeks believed some of them, like Enceladus, to lay buried from that time under the earth, and that their tormented quivers resulted in earthquakes and volcanic eruptions. Greek mythology also features the cyclopes - well remembered for their encounter with Odysseus in Homer's Odyssey - giants (though not gigantes) with only one eye. The titans were as well often imagined to be of great size and strength, hence the word titanic.
Herodotus in Book 1, Chapter 68, describes how the Spartans uncovered in Tegea the body of Orestes which was seven cubits long -- around 10 feet. In his book The Comparison of Romulus with Theseus Plutarch describes how the Athenians uncovered the body of Theseus, which was of more than ordinary size. The kneecaps of Ajax were exactly the size of a discus for the boy's pentathlon, wrote Pausanias. A boy's discus was about twelve centimeters in diameter, while a normal adult patella is around five centimeters, suggesting Ajax may have been around 14 feet tall.
In Germanic mythologies - of which Norse mythology, due to its extensive Icelandic sources, is the only one well recorded - the giants (jotnar in Old Norse, a cognate with ettin) are often opposed to the gods. They come in different classes, such as frost giants (hrimpursar) fire giants (eldjotnar) and mountain giants (bergrisar). The giants are the origin of most of the monsters in Norse mythology (e.g. the Fenrisulfr), and in the eventual, apocalyptic battle of Ragnarok the giants will storm Asgard, the home of the gods in Heaven, and defeat them in war, thus bringing about the end of the world. Even so, the gods themselves related to the giants by many marriages, and there are giants such as Aegir, Mimir and Skaoi, who bear little difference in status to them. Norse mythology also holds that the entire world of men was once created from the flesh of Ymir - a giant of cosmic proportions, by some considered to share a root with the name Yama of Indo-Iranian mythology. A bergrisi appears as a supporter on the coat of arms of Iceland.
In folklore from all over Europe, giants were believed to have built the remains of previous civilizations. Saxo Grammaticus, for example, argues that giants had to exist, because nothing else would explain the large walls, stone monuments, and statues that we know were the remains of Roman construction. Similarly, the Old English poem Seafarer speaks of the high stone walls that were the work of giants. Even natural geologic features such as the massive basalt columns of the Giant's Causeway on the coast of Northern Ireland were attributed to construction by giants. Giants provided the least complicated explanation for such artifacts.
In Basque mythology, giants appear as jentilak and mairuak (Moors), and were said to have raised the dolmens and menhirs. After Christianization, they were driven away, and the only remaining one is Olentzero, a coalmaker that brings gifts on Christmas Eve.
Tales of combat with giants were a common feature in the folklore of Wales, Scotland and Ireland. Some Irish giants such as Fionn mac Cumhaill (Finn McCool) were considered benevolent and well liked by humans. Celtic giants also figure in Breton and Arthurian romances, and from this source they spread into the heroic tales of Torquato Tasso, Ludovico Ariosto, and their follower Edmund Spenser. In the small Scottish village of Kinloch Rannoch, a local myth to this effect concerns a local hill that apparently resembles the head, shoulders, and torso of a man, and has therefore been termed 'the sleeping giant'. Apparently the giant will awaken only if a specific musical instrument is played near the hill.
Many giants in British folklore were noted for their stupidity. A giant who had quarreled with the Mayor of Shrewsbury went to bury the city with dirt; however, he met a shoemaker, carrying shoes to repair, and the shoemaker convinced the giant that he had worn out all the shoes coming from Shrewsbury, and so it was too far to travel.
Other British giants were told in stories of how they threw stones at each other. This was used to explain many great stones on the landscape.
Giants figure in a great many fairy tales and folklore stories, such as Jack and the Beanstalk, The Giant Who Had No Heart in His Body, Nix Nought Nothing, Robin Hood and the Prince of Aragon, Young Ronald, and Paul Bunyan. Ogres and trolls are humanoid creatures, sometimes of gigantic stature, that occur in various sorts of European folklore. An example of another folklore giant is Rubezahl, a kind giant in German folklore who lived in the Giant Mountains (nowadays on the Czech-Polish border).
Aside from mythology and folklore (see Tall tales), mysterious remains of giants have been found in America. Giants are usually classified as human-like remains that are 7'-5" or more in height. The book Forbidden Land by Robert Lyman (1971) recounts the following finds:
Aside from in Forbidden Land, we can find other unverified examples or legends about the remains of giants: