The first author to describe the coast of Holland and Flanders was the geographer Pytheas, who noted in c. 325 BC that in these regions, "more people died in the struggle against water than in the struggle against men."[59] During the Gallic Wars, the area south and west of the Rhine was conquered by Roman forces under Julius Caesar from 57 BC to 53 BC.[58] Caesar describes two main Celtic tribes living in what is now the southern Netherlands: the Menapii and the Eburones. Under Augustus, the Roman Empire would conquer the entirety of the modern day Netherlands, incorporating it into the province of Germania Antiqua in 7 BC, but would be repelled back across the Rhine after the Battle of Teutoburg Forest in 9 AD, with the Rhine becoming fixed as Rome's permanent northern frontier around 12 AD. Notable towns would arise along the Limes Germanicus: Nijmegen and Voorburg. In the first part of Gallia Belgica, the area south of the Limes became part of the Roman province of Germania Inferior. The area to the north of the Rhine, inhabited by the Frisii, remained outside Roman rule, while the Germanic border tribes of the Batavi and Cananefates served in the Roman cavalry.[60] The Batavi rose against the Romans in the Batavian rebellion of 69 AD but were eventually defeated. The Batavi later merged with other tribes into the confederation of the Salian Franks, whose identity emerged in the first half of the third century.[61] Salian Franks appear in Roman texts as both allies and enemies. They were forced by the confederation of the Saxons from the east to move over the Rhine into Roman territory in the fourth century. From their new base in West Flanders and the Southwest Netherlands, they were raiding the English Channel. Roman forces pacified the region but did not expel the Franks, who continued to be feared at least until the time of Julian the Apostate (358) when Salian Franks were allowed to settle as foederati in Texandria.[61] Early Middle Ages (411–1000) Main articles: Frankish Kingdom and Frisian Kingdom Franks, Frisians and Saxons, c. 716 AD After the Roman government in the area collapsed in roughly the year 406,[62] the Franks expanded their territories into numerous kingdoms. By the 490s, Clovis I had conquered and united all these territories in the southern Netherlands in one Frankish kingdom, and from there continued his conquests into Gaul. During this expansion, Franks migrating to the south (modern territory of France and Walloon part of Belgium) eventually adopted the Vulgar Latin of the local population.[56] A widening cultural divide grew with the Franks remaining in their original homeland in the north (i.e. the southern Netherlands and Flanders), who kept on speaking Old Frankish, which by the ninth century had evolved into Old Low Franconian or Old Dutch.[56] A Dutch-French language boundary hence came into existence.[56][63] Frankish expansion (481 to 870 AD) To the north of the Franks, climatic conditions improved, and during the Migration Period Saxons, the closely related Angles, Jutes, and Frisii settled the coast.[64] Many moved on to England and came to be known as Anglo-Saxons, but those who stayed would be referred to as Frisians and their language as Frisian.[64] Frisian was spoken along the entire southern North Sea coast. By the seventh century, a Frisian Kingdom (650–734) under King Aldegisel and King Redbad emerged with Traiectum (Utrecht) as its centre of power,[64][65] while Dorestad was a flourishing trading place.[66][67] Between 600 and around 719 the cities were often fought over between the Frisians and the Franks. In 734, at the Battle of the Boarn, the Frisians were defeated after a series of wars. With the approval of the Franks, the Anglo-Saxon missionary Willibrord converted the Frisian people to Christianity and established the Archdiocese of Utrecht. However, his successor Boniface was murdered by the Frisians in 754. Rorik of Dorestad, Viking ruler of Friesland (romantic 1912 depiction) The Frankish Carolingian empire controlled much of Western Europe. In 843, it was divided into three parts—East, Middle, and West Francia. Most of present-day Netherlands became part of Middle Francia, which was a weak kingdom and subject to numerous partitions and annexation attempts by its stronger neighbours. It comprised territories from Frisia in the north to the Kingdom of Italy in the south. Around 850, Lothair I of Middle Francia acknowledged the Viking Rorik of Dorestad as ruler of most of Frisia. When the kingdom of Middle Francia was partitioned in 855, the lands north of the Alps passed to Lothair II and subsequently were named Lotharingia. After he died in 869, Lotharingia was partitioned, into Upper and Lower Lotharingia, the latter comprising the Low Countries that became part of East Francia in 870. Around 879, another Viking expedition led by Godfrid, Duke of Frisia, raided the Frisian lands. Resistance to the Vikings, if any, came from local nobles, who gained in stature as a result, and that laid the basis for the disintegration of Lower Lotharingia into semi-independent states. One of these local nobles was Gerolf of Holland, who assumed lordship in Frisia, and Viking rule came to an end.[68] High Middle Ages (1000–1384) Main article: History of urban centres in the Low Countries A medieval tomb of the Brabantian knight Arnold van der Sluijs The Holy Roman Empire ruled much of the Low Countries in the 10th and 11th century but was not able to maintain political unity. Powerful local nobles turned their cities, counties and duchies into private kingdoms that felt little sense of obligation to the emperor.[69] Holland, Hainaut, Flanders, Gelre, Brabant, and Utrecht were in a state of almost continual war or paradoxically formed personal unions. As Frankish settlement progressed from Flanders and Brabant, the area quickly became Old Low Franconian (or Old Dutch). Around 1000 AD, agrarian conditions started to improve, which lead to increase in population, reclamation of wasteland by farmers, and steady growth of trade and industry.[62] Towns grew around monasteries and castles, and a mercantile middle class began to develop in these urban areas, especially in Flanders, and later Brabant. Wealthy cities started to buy certain privileges for themselves from the sovereign. Around 1100 AD, farmers from Flanders and Utrecht began draining and cultivating uninhabited swampy land in the western Netherlands, making the emergence of the County of Holland as the centre of power possible. The title of Count of Holland was fought over in the Hook and Cod Wars between 1350 and 1490. The Cod faction consisted of the more progressive cities, while the Hook faction consisted of the conservative noblemen. These noblemen invited Duke Philip the Good of Burgundy to conquer Holland.[citation needed] Burgundian, Habsburg and Spanish Habsburg Netherlands (1384–1581) Main articles: Burgundian Netherlands, Habsburg Netherlands, and Spanish Netherlands