The history of Denmark as a unified kingdom began in the 8th century, but prehistoric cultures populated the area for about 12,000 years, since the end of the last ice age. Historic descriptions of the area and people from around 500 AD include writings by Jordanes and Procopius. The kingdom arose before the Christianization of the Danes c. 960 AD. The Viking kings Gorm the Old and Harald Bluetooth from that time are predecessors of today's king, Frederik X, thus the monarchy of Denmark is the oldest in Europe.
Denmark's history was shaped by its location between the North and Baltic seas and between Sweden and Germany. This location provided economic benefits and mutual struggles for control of the Baltic Sea (). For example, it had long disputes with Sweden over Skånelandene and with Germany over Schleswig (a Danish fief) and Holstein (a German fief). Eventually, Denmark lost these conflicts and ceded Skåneland to Sweden and later Schleswig-Holstein to the German Empire. After Norway seceded in 1814, Denmark retained control of the old Norwegian colonies of the Faroe Islands, Greenland and Iceland. During the 20th century, Iceland gained independence, Greenland and the Faroes became integral parts of the Kingdom of Denmark and North Schleswig reunited with Denmark in 1920 after a referendum. During World War II, Denmark was occupied by Nazi Germany, but was liberated by British forces of the Allies in 1945The remote Danish island of Bornholm in the Baltic Sea was liberated by Soviet forces of the Allies. This led to some political turmoil and conflict, occasionally resurfacing in modern times. and soon joined the United Nations. With the emergence of the Cold War, Denmark was a founding member of the military alliance NATO in 1949.
Prehistory
The Scandinavian region has been populated by several prehistoric cultures and people for about 12,000 years, since the end of the last ice age. During the ice age, all of Scandinavia was covered by glaciers most of the time, except for the southwestern parts of what we now know as Denmark. When the ice began retreating, the barren tundras were soon inhabited by reindeer and elk, and Ahrenburg and Swiderian hunters from the south followed them here to hunt occasionally. Due to lower sea levels, the area called Doggerland between Great Britain and today's Jutland peninsula was inhabited by tribes of hunter-gatherers. As the climate warmed, meltwater shaped the land, the submerged Doggerland and more stable flora and fauna gradually emerged in Scandinavia. The first permanent human settlers in Scandinavia were the Maglemosian people, residing in seasonal camps and exploiting the land, sea, rivers and lakes. The approximate geography of today's Denmark had taken shape by around 6,000 BC.
Denmark has some unique natural conditions for preservation of artifacts, providing a rich and diverse archeological record from which to understand the prehistoric cultures of this area.
Stone and Bronze Age
The Weichsel glaciation covered all of Denmark most of the time, except the western coasts of Jutland. It ended around 13,000 years ago, allowing humans to move back and settle there. Over a few thousand years, the vegetation changed from tundra to light forest, and various animal species appeared, including megafauna. Early prehistoric human cultures uncovered in modern Denmark include the Maglemosian culture (9,500–6,000 BC); the Kongemose culture (6,000–5,200 BC), the Ertebølle culture (5,300–3,950 BC), and the Funnelbeaker culture (4,100–2,800 BC).
During this so-called Boreal period, human groups here were very small and scattered living from hunting of reindeer and other land mammals and gathering whatever fruits the climate was able to offer. Around 8,300 BC the temperature rose sharply, reaching around 15 degrees Celsius (59 degrees Fahrenheit) in summer; the vegetation changed into dense forests of aspen, birch and pine and the reindeer moved north, while aurochs and elk arrived from the south. The oldest set of human bones found in Denmark and oldest bog body found in the world is the Koelbjerg Man, dated to the time of the Maglemosian culture around 8,000 BC. With a continuing rise in temperature oak, elm and hazel arrived in Denmark around 7,000 BC. Boar, red deer, and roe deer also began to abound.Jensen 2003:12–18
A burial from Bøgebakken at Vedbæk dates to c. 6,000 BC and contains 22 persons – including four newborns and one toddler. Eight of the 22 had died before reaching 20 years of age – testifying to the hardness of hunter-gatherer life in the cold north.Jensen 2003:24 Based on estimates of the amount of game animals, scholars estimate the population of Denmark to have been between 3,300 and 8,000 persons in the time around 7,000 BC.Jensen 2003:32 It is believed that the early hunter-gatherers lived nomadically, exploiting different environments at different times of the year, gradually shifting to the use of semi permanent base camps.Jensen 2003:34
The rising temperatures caused a rise in sea levels so that during the Atlantic period Denmark evolved from a contiguous landmass around 11,000 BC to a series of islands by 4,500 BC. The inhabitants then shifted to a seafood-based diet, which allowed the population to increase.
After agriculture arrived in Central Europe, for 1,500 years Scandinavia remained Mesolithic in the Ertebølle culture. Around 4,000 BC it was replaced by Funnelbeaker neolithic farmers which left many dolmens and rock tombs (especially passage graves). After about 1,000 years, Steppe herder descendents began to arrive from Eastern Europe. They descended from peoples from the Pontic–Caspian steppe who flooded Europe and gave rise to Corded Ware culture and its local variant, the Single Grave culture. The Nordic Bronze Age period in Denmark, from about 1,500 BC, featured a culture that buried its dead, with their worldly goods, beneath burial mounds. The many finds of gold and bronze from this era include beautiful religious artifacts and musical instruments, and provide the earliest evidence of social classes and stratification.
Iron Age
During the Pre-Roman Iron Age (from the 4th to the 1st century BC), the climate in southern Scandinavia became cooler and wetter, limiting agriculture. Humans migrated south to Germania. People also began to extract iron from ore in peat bogs. Celtic culture existed in the area as in much of northwest Europe, and survives in some place names.
The Roman Empire excluded Denmark but traded with people there, as attested by finds of Roman coins. Some Danish warrior-aristocrats served in the Roman army.Birger Storgaard, Cosmopolitan aristocrats, pp. 106–125 in: The Spoils of Victory – The North in the shadow of the Roman Empire, Nationalmuseet, 2003. . The earliest known runic inscriptions date to c. 200 AD. In the last century BC, depletion of cultivated land apparently contributed to migrations in northern Europe and conflict between Teutonic tribes and Roman settlements in Gaul. Roman artifacts are especially common in finds from the 1st century. Occasionally, animals and humans were sacrificed and bodies were immersed in bogs. Some bog bodies such as Tollund Man and Grauballe Man emerged very well-preserved in , providing information about the cultures in Denmark during this period.
From around the 5th to the 7th century, Northern Europe experienced mass migrations. This period and its material culture are referred to as the Germanic Iron Age.
Middle Ages
Earliest literary sources
In his description of Scandza (from the 6th-century work, Getica), the ancient writer Jordanes says that the Dani were of the same stock as the Suetidi (Swedes, Suithiod?) and expelled the Heruli and took their lands.
The Old English poems Widsith and Beowulf, as well as works by later Scandinavian writers — notably by Saxo Grammaticus (c. 1200) — provide some of the earliest references to Danes.
Viking Age
With the beginning of the Viking Age in the 9th century, the prehistoric period in Denmark ends. The Danish people were among those known as Vikings, during the 8th–11th centuries. Viking explorers first discovered and settled in Iceland in the 9th century, on their way from the Faroe Islands. From there, Greenland and Vinland (probably Newfoundland) were also settled. Utilizing their great skills in shipbuilding and navigation they raided and conquered parts of France and the British Isles.
They also excelled in trading along the coasts and rivers of Europe, running trade routes from Greenland in the north to Constantinople in the south via Russian and Ukrainian rivers, most notably along the River Dnieper and via Kiev, then being the capital of Kievan Rus, which was founded by Viking conquerors. The Danish Vikings were most active in Britain, Ireland, France, Spain, Portugal and Italy where they raided, conquered and settled (their earliest settlements included sites in the Danelaw, Ireland and Normandy). The Danelaw encompassed the Northeastern half of what now constitutes England, where Danes settled and Danish law and rule prevailed. Prior to this time, England consisted of approximately seven independent Anglo-Saxon kingdoms. The Danes conquered (terminated) all of these except for the kingdom of Wessex. Alfred the Great, king of Wessex, emerged from these trials as the sole remaining English king, and thereby as the first English Monarch.
In the early 9th century, Charlemagne's Christian empire had expanded to the southern border of the Danes, and Frankish sources (e.g. Notker of St Gall) provide the earliest historical evidence of the Danes. These report a King Gudfred, who appeared in present-day Holstein with a navy in 804 where diplomacy took place with the Franks; In 808, King Gudfred attacked the Obotrites and conquered the city of Reric whose population was displaced or abducted to Hedeby. In 809, King Godfred and emissaries of Charlemagne failed to negotiate peace, despite the sister of Godfred being a concubine of Charlemagne, and the next year King Godfred attacked the Frisians with 200 ships.
Viking raids along the coast of France and the Netherlands were large-scale. Paris was besieged and the Loire Valley devastated during the 10th century. One group of Danes was granted permission to settle in northwestern France under the condition that they defend the place from future attacks. As a result, the region became known as "Normandy" and it was the descendants of these settlers who conquered England in 1066.
The oldest parts of the defensive works of Danevirke near Hedeby at least date from the summer of 755 and were expanded with large works in the 10th century. The size and number of troops needed to man it indicates a quite powerful ruler in the area, which might be consistent with the kings of the Frankish sources. In 815 AD, Emperor Louis the Pious attacked Jutland apparently in support of a contender to the throne, perhaps Harald Klak, but was turned back by the sons of Godfred, who most likely were the sons of the above-mentioned Godfred. At the same time St. Ansgar travelled to Hedeby and started the Catholic Christianisation of Scandinavia.
Gorm the Old was the first historically recognized ruler of Denmark, reigning from to his death . He ruled from Jelling, and made the oldest of the Jelling Stones in honour of his wife Thyra. Gorm was born before 900 and died . His rule marks the start of the Danish monarchy and royal house (see Danish monarchs' family tree).