Area settled by the Alamanni, and sites of Roman-Alamannic battles, 3rd to 6th centuryAlemannic belt mountings, from a 7th century grave in the grave field atWeingarten.

The Alamanni, Allemanni, or Alemanni were originally an alliance of Germanic tribes located around the upper Rhine river (Germany). One of the earliest references to them is the cognomen Alamannicus assumed by Roman Emperor Caracalla, who ruled the Roman Empire from 211–217 and claimed thereby to be their conqueror. The nature of this alliance and their previous tribal affiliations remain uncertain. The alliance was aggressive in nature, attacking the Roman province of Germania Superior whenever it could^{[citation needed]}. Generally its strategy with respect to the Empire was similar to that of the Franks.

From the 1st century, the Rhine had become the border between Roman Gaul and tribal Germania. Germanic peoples, Celts, and tribes of mixed Celto-Germanic ethnicity were settled in the lands along both banks. The Romans divided these territories into two districts, Germania Inferior and Germania Superior situated along the lower (north) and upper (south) Rhinerespectively.

Upper Germania included the region between the upper Rhine and the upper Danube, (the Black Forest region that was larger than today: see Hercynian Forest). The Romans called this the Agri Decumates, (i.e. “Decumates territories”), a name of unknown origin. Some scholars have translated the expression as “the ten cantons”, but whose cantons of what entity is not known.

The exterior Roman fortified border around the area of Germania Superior was called the Limes Germanicus. The assembled warbands of the Alamanni frequently crossed the limes, attacking Germania Superior and moving into the Agri Decumates. As a confederation, from the 5th century, they settled the Alsace and expanded into the Swiss Plateau, as well as parts of what are now Bavaria and Austria, reaching the valleys of the Alps by the 8th century.

According to Historia Augusta the confederates in the 3rd century were still simply called Germani. Proculus, an imperial usurper in 280, derived some of his popularity in Gaul by his battle successes against the Alamanni. The Alamanni, thereafter became the nation of Alamannia, that was sometimes independent, but more often was ruled by the Franks. The name of Germany and the German language, in French, Allemagne, allemand, in Portuguese Alemanha, alemão, in Spanish Alemania, alemán, and in Welsh (Yr) Almaen, almaeneg are derived from the name of this early Germanic nation. Persian and Arabic also designate Germans Almaani, and Germany asAlmaan in Persian and Almaania in Arabic. In Turkish, German is Alman and Germany is Almanya.

The region of the Alamanni was always somewhat sprawling and comprised a number of different districts, reflecting its mixed origins. In theEarly Middle Ages its territories were divided between the Diocese of Strassburg, which dates from about 614, the territory of Augusta Vindelicorum (Augsburg) from 736, the Moguntiacum (Mainz) archdiocese from 745, and of Basilia (Basel) from 805. Its distinctive laws were codified under Charlemagne as the Duchy of Alamannia in Swabia. Today the descendants of the Alamanni are divided between parts of four nations: France (Alsace), Germany (Swabia and parts of Bavaria), Switzerland and Austria, and the German spoken in those regions has distinctive regional dialects.

I thought i should post a map that gives an aproximate time period of what it claims to reprecent. Ca 500 AD.

Note that an exact map like this cant be done and in other timeperiods other tribal constellations would exist and tribes would be in other places.

Also, the Germanic tribes where not alone in all these areas with a few exeptions.

You might add Sviar, Gauti and Guti in Sweden too (as well as the Dani in todays southern Sweden, Scania and Hallandia + more)..

Migration Period:

During the 5th century CE, as the Western Roman Empire lost military strength and political cohesion, numerous Germanic peoples, under pressure from population growth and invading Asian groups, began migrating en masse in far and diverse directions, taking them to Great Britain and far south through present day Continental Europe to the Mediterranean and northern Africa. Over time, this wandering meant intrusions into other tribal territories, and the ensuing wars for land escalated with the dwindling amount of unoccupied territory. Wandering tribes then began staking out permanent homes as a means of protection. Much of this resulted in fixed settlements from which many, under a powerful leader, expanded outwards. A defeat meant either scattering or merging with the dominant tribe, and this continual process of assimilation was how nations were formed. In Denmark the Jutes merged with the Danes, in Sweden the Geats merged with the Swedes. In England, the Angles merged with the Saxons and other groups (notably the Jutes), as well as absorbing a huge number of natives, to form the Anglo-Saxons.

A direct result of the Roman retreat was the disappearance of imported products like ceramics and coins, and a return to virtually unchanged local Iron Age production methods. According to recent views this has caused confusion for decades, and theories assuming the total abandonment of the coastal regions to account for an archaeological time gap that never existed have been renounced. Instead, it has been confirmed that the Frisian graves had been used without interruption between the 4th and 9th century CE and that inhabited areas show continuity with the Roman period in revealing coins, jewellery and ceramics of the 5th century. Also, people continued to live in the same three-aisled farmhouse, while to the east completely new types of buildings arose. More to the south, in Belgium, archeological results of this period point to immigration from the north. 

Some coming articles on queue:

1. Vikings and Normans
2. The Normans, history,arms,tactics
3. Origin of the Germanic peoples - Bronze Age
4. Origin of the Germanic peoples - Early Iron Age
5. At the Time of the Tollund Man What was the Tollund Man’s Life like? - Early Iron Age
6. Origin of the Germanic peoples - Roman Empire Period:
7. NORMANS II: The Norman military machine
8. Everyday Life in the Iron Age What was Life like in the Iron Age?
9. Weaponry and Warfare in the Iron Age
10. Origin of the Germanic peoples - Migration Period
11. Origin of the Germanic peoples - Role In The Fall Of Rome:
12. Origin of the Germanic peoples - Early Middle Ages