This Gaelic expansion caused some resentment among their neighboring Celtic tribes. In124 BC the Gaelic tribe of Massaliots called upon the Roman general Flaminius to mediate a dispute with the Ligurians. The latter refused the mediation with a series of insults and the Roman legion assisted the Massaliots in defeating them. In reward, the Romans were allowed to build a colony called Aqua Sextius on the Rhone River. This brought an emigration of Roman people into Gaul. By 121 BC the Romans ruled the entire province and another city was built at Narbo. Twenty years later this city was attacked by forces of Cimbri and Teuton tribes, but were repelled by the Roman forces. In 60 BC a Gaelic tribe called the Aedvi formed an alliance with the Romans to assist in the defense of the Roman province of Narbonne, but the Teutons retaliated against this betrayal of Celtic people and defeated them in a fierce battle. As a result, Rome sent a new governor to Narbonne named Julius Caesar.
Julius carried out an eight year campaign to conquer all of Gaul. By 50 BC the tribes had all been subdued and it became a Roman province. Vercingetroix, the leader of the Celtic resistance, was captured and carried to Rome where he was publicly executed in 46 BC. Caesar returned to Rome a hero in 45 BC, but political elements within the Senate feared the rising power of the popular Emperor and assassinated him one year later.
Augustus succeeded him and reorganized the governmental structure of Gaul in 40 BC. Narbonesis was made an official colony with a municipal government directly affiliated with Rome. The remainder of Gaul was divided into three provinces: Belgica, Lugudunesis and Aquitania. He allowed the native Celtic tribes to be self-governing, each with their own central town for marketing. Their Druidic customs were allowed to continue so long as they did not conflict with the laws of the Provincial Government. Under the governorship of Augustus additional colonies were established in Gaul and Spain. By the year 48 CE (Christian Era) the nobles of Gaul were allowed to sit in the Roman Senate.
In 7 BC Augustus launched a campaign against the tribes in Germany. The Druids were able to maintain a strong defense finally annihilated the Roman army at Teutonburger Forest in 9 CE. This ended Roman rule in northern Germany except for Batavia. In 69 CE a prophetess named Veleda aroused the Batavians and surrounding tribes to revolt against the Romans, but were suppressed by the forces of the Roman legions.
Meanwhile, the Romans continued their expansion efforts to the west. In 42 CE the Emperor Claudius conquered the southern half of the Celtic island of Albion, which he renamed "Britannia", after the native tribe of Britons. In the year 50 he built the city of Camalodinum (Colchester). During this campaign Caractacus, the king of the Silures (in Wales), was betrayed and taken prisoner. Claudius sent him to Rome for imprisonment. The Celtic Queen Boadicea rallied the Celts in an attempt to drive the Romans from their shores in 61 CE. The tribal warriors captured the cities of Londonium and Verulamium, but were finally overcome by Roman forces a year later.
In the year 80 the Roman governor Agricola reached the Forth and Clyde in western Britain, and sailed his ship around the entire island to familiarize himself with its terrain. He is credited with bringing Roman civilization to the cities of Britain. The Emperor Hadrian arrived on the shores of Britain in 120 and proceeded to build his famous wall between Solway and Tyne. This marked the northernmost border of the Roman Empire. The project of building the wall and its defensive works kept the Roman legions occupied in northern Britain for over 20 years.
In the centuries that followed, Roman civilization became well established in Britain. More cities were built and highways were constructed to connect all the centers of Roman trade. All the modern technology and engineering were introduced to the northern colonies, including aqueducts for running water and a flow of trade products from around the Roman Empire. The native tribes were forced to the north and west of the islands, with occasional attacks against the encroachment of foreign civilization. In 208 the Emperor Severus came to Britain to suppress an invasion of Picts on the northern borders and died three years later at Eboracum (York). The succeeding Emperor, Caracall, attempted to unite the vast provinces of the Empire by bestowing Roman citizenship to everyone in the entire Roman Empire, including those in the "civilized" portion of Britannia.
About the year 200 the German tribes began to form confederations which moved to the southwest to attack the Roman frontier. The Burgundians and Vandals subdued Gaul, the Lombards claimed the northern Alps, and Spain was taken by the Visigoths. Tribes of Goths attached the provinces of Greece at Macedonia in 250 CE. In 271 a confederation of Celtic tribes descended into Italy but were defeated by Marcus Aurelius, who built a defensive wall around the city of Rome. Another arm of this confederation, led by the Alamanni, swept into Gaul and killed over 60,000 people in the Roman province. In 277 the German tribes were defeated by General Probos, who then enlisted 16,000 of the Celtic warriors into the Roman forces as "foederati".
In about the year 310 the Emperor Maxentius was haunted by a dream of the most beautiful woman in the world who awaited him in a fair island to the west. Following his dream, he arrived at Londonium and was greeted by Octaf, High King of Britain. At his side was the woman of his dream -- Elen, the daughter of Octaf. In a short time they were wed and the royal family of Britain became heirs to the throne of Rome. Maxen was a kind and generous man who easily won the hearts of the Britons as they rose to a time of great prosperity and good government. The Roman Emperor remained in Britain for many years until word reached him that a political rival had taken the throne of Rome in his absence.
Queen Elen amassed a mighty army of Celts to defend the crown of their beloved Emperor. Peasants, farmers, craftsmen and Druids all joined the warriors of Britain and sailed across the sea to Rome. The massive army was led by the cousin of the Queen, a prince named Conan Meriadoc. On their way the army reclaimed the lands of Gaul, Spain, Germany and Italy for their Emperor. When Maxentius approached the city of Rome, he was joyously welcomed by the citizens. Not a man or woman was killed in the ensuing struggle except for the usurper who had claimed the throne. Maxen and Elen remained in Rome, and Conan Meriadoc was named King over the Celtic lands of Armorica.