Throughout Europe in the Middle Ages, different groups moved from one location to another.  Sometimes, the purpose was conquest, sometimes raiding, and sometimes it involved a quest for a better life and the intent was to settle, rather than conquer, new lands.

But usually somebody was already there.  The map at right show the paths of various groups from Roman times to through the Middle Ages. After the sack of Rome in 410 (see my post here: http://www.sarahwoodbury.com/the-fall-of-rome/) tribes were on the move all through Europe:

Angles/Saxons/Jutes:  These three groups derived from Denmark and Germany.  “Following the departure of the Romans in A.D.410 and after the sacking of Rome, Britain was left unprotected. The distant dominions frantic call to Rome went unheard. Mutiny spread through the ranks of the British defenders remaining who were now descendants of Roman stock. Britain in desperation declared independence from Rome and defended itself the best way it could. Despite this sudden change in fortune for Britain, the Roman lifestyle continued, if on a downward path for the next fifty years. The departure of the Romans did not go un-noticed by the Picts, Scots and especially the Saxons, who saw Britain as a prosperous and plunderable asset.”  http://www.battle1066.com/saxons.shtml  The Saxons waves continued until the 800s, when they’d conquered all of England, pushing the Welsh and Scots to the edges of the map.

Franks:  The Franks originated in what is now Belgium, but spread post-Rome south to France.  “Clovis extends his power from the Somme down to the Loire by using an unscrupulous blend of warfare, intrigue and murder to assert his authority over other Frankish tribes in the region. He then sucessfuly demands tribute from the Burgundians in the southeast and, more significantly, drives the Visigoths from the southwest. By 507 the whole of France, except a narrow strip along the Mediterranean, is his acknowledged realm.”
Read more: http://www.historyworld.net/wrldhis/PlainTextHistories.asp?historyid=ab74#ixzz1ABfvBH4X

Goths/Visigoths/Ostragoths:  The Goths overall are a German people, with the Visigoths coming from Western Germany and the Ostrogoths from Eastern Germany.  “They originated in Scandinavia, but by the 2nd century of the Christian Era had moved into what is now Southern Russia. The Goths had adopted the habit of fighting on horseback. This arose from the fact that the first area the Goths invaded in the 2nd century AD were the vast plains of Eastern Europe and southern Russia.  . . .  The Goths first burst upon the scene of history in the 3rd Century, when they swarmed out of Southern Russia by both land and sea to beset the Roman Empire. After an heroic struggle, the Romans managed to drive them back to work on their military techniques a little more. In the mid-4th century the Goths were attacked by even wilder peoples, like the Huns. The Visigoths sought security within the boundries of the Roman Empire, offering to help defend the Balkans in return for land, but the Emperor Valens spurned their offer. So they invaded, and in 378 overwhelmed a Roman army at Adrianople, using cavalry in combination with a fortified camp. The victory seems to have surprised the Visigoths almost as much as it did the Romans, for they agreed to settle in the Balkans and help defend them against other tribes. Within a century, the Visigoths had drifted westwards, to settle in southern Gaul (modern France) and Spain, where they set up a kingdom of their own.”  http://www.hyw.com/books/history/goths.htm

Huns:   “Arriving on the fringes of the Roman Empire in the late fourth century, riding their war horses out of the great steppes of Asia, they struck fear into Germanic barbarians and Romans alike. Some scholars believe that they had earlier moved against the Chinese Empire but were turned away and swept to wards Rome instead. As they approached the Black Sea and conquered the Ostrogoths, they also drove the Visigoths across the Danube into the Roman Empire and caused the crisis that led to the astounding defeat of the Roman army under the Emperor Valens at Adrianople in 378 AD.

Those early Huns, using the traditional tactics of mounted archers, seemed like monsters from the darkness to their more civilized contemporaries. The Roman historian Ammianus Marcellinus, writing at the end of the fourth century, described their savage customs and elaborated on their military tactics:

“The nation of the Huns…surpasses all other barbarians in wildness of life….And though [the Huns] do just bear the likeness of men (of a very ugly pattern), they are so little advanced in civilization that they make no use of fire, nor any kind of relish, in the preparation of their food, but feed upon the roots which they find in the fields, and the half-raw flesh of any sort of animal. I say half-raw, because they give it a kind of cooking by placing it between their own thighs and the backs of their horses….”  http://members.gcronline.com/attila/history.htm  He was probably biased.

Vandals:  “The Vandals first entered collapsing Roman Empire in the winter of 409 AD, when they crossed the frozen Rhine river with a group of Alans and Sueves. They were taking advantage of a rebellion within the Empire which kept the Romans from defending themselves well. The Vandals (with the Alans and Sueves) slowly travelled south through Gaul (France), looting and fighting as they went. When they reached the Pyrenees mountains that separate France from Spain, they were actually invited into Spain by one of the rebel leaders, in exchange for helping him with his rebellion.
After this rebellion failed, the Vandals were left on their own in Spain. They took over the southern part of Spain in about 411 AD. A Visigothic attack in 415 AD weakened them but did not destroy them.

By 429 AD the Vandals decided to move to Africa instead of Spain, and ferried all 80,000 of their people across the Straits of Gibraltar in boats. Under their king Gaiseric, the Vandals established a kingdom in Africa, which they used as a base for piracy around the Mediterranean for a hundred years. They set up an Arian church, minted their own coins, and had diplomatic relations with other Mediterranean kingdoms.
In 533, however, the Roman Emperor Justinian sent his general Belisarius to reconquer Africa for Rome. When Belisarius succeeded, that was the end of the Vandals.”  http://www.historyforkids.org/learn/medieval/history/earlymiddle/vandals.htm