Context: Gallia Belgica (Belgic Gaul) was a province of the Roman empire located in Belgium, in the northern and eastern parts of Roman Gaul.
It began as one of the three main provinces of Gaul (known as the "Tres Galliae" the other two being Gallia Aquitania and Gallia Lugdunensis) described by its Roman conqueror Julius Caesar. An official Roman province was later created by emperor Augustus in 22 BC., Gaul (Latin: "Gallia") was a region of Western Europe during the Iron Age that was inhabited by Celtic tribes, encompassing present day France, Luxembourg, Belgium, most of Switzerland, Northern Italy, as well as the parts of the Netherlands, Central Italy and Germany on the west bank of the Rhine. It covered an area of 190,800 mi² or 494,169 km². According to the testimony of Julius Caesar, Gaul was divided into three parts: Gallia Celtica, Belgica and Aquitania.
Archaeologically, the Gauls were bearers of the La Tène culture, which extended across all of Gaul, as well as east to Raetia, Noricum, Pannonia and southwestern Germania during the 5th to 1st centuries BC.
During the 2nd and 1st centuries BC, Gaul fell under Roman rule: Gallia Cisalpina was conquered in 203 BC and Gallia Narbonensis in 123 BC. Gaul was invaded after 120 BC by the Cimbri and the Teutons, who were in turn defeated by the Romans by 103 BC. Julius Caesar finally subdued the remaining parts of Gaul in his campaigns of 58 to 51 BC., Gaius Julius Caesar (13 July 100 BC  15 March 44 BC), known as Julius Caesar, was a Roman politician, general, and notable author of Latin prose. He played a critical role in the events that led to the demise of the Roman Republic and the rise of the Roman Empire., Borders are geographic boundaries of political entities or legal jurisdictions, such as governments, sovereign states, federated states, and other subnational entities. Some borderssuch as a state's internal administrative border, or inter-state borders within the Schengen Areaare often open and completely unguarded. Other borders are partially or fully controlled, and may be crossed legally only at designated border checkpoints and border zones may be controlled. Mostly contentious, borders may even foster the setting up of buffer zones. A difference has also been established in academic scholarship between border and frontier, the latter denoting a state of mind rather than state boundaries., Strabo ("Strabn"; 64 or 63 BC) was a Greek geographer, philosopher, and historian who lived in Asia Minor during the transitional period of the Roman Republic into the Roman Empire., Commentarii de Bello Gallico, also simply Bellum Gallicum, is Julius Caesar's firsthand account of the Gallic Wars, written as a third-person narrative. In it Caesar describes the battles and intrigues that took place in the nine years he spent fighting the Germanic peoples and Celtic peoples in Gaul that opposed Roman conquest., The Netherlands  is the main constituent country of the Kingdom of the Netherlands. It is a densely populated country located in Western Europe with three island territories in the Caribbean. The European part of the Netherlands borders Germany to the east, Belgium to the south, and the North Sea to the northwest, sharing maritime borders with Belgium, the United Kingdom, and Germany. The largest cities in the Netherlands are Amsterdam, Rotterdam, The Hague and Utrecht. Amsterdam is the country's capital, while The Hague holds the Dutch seat of government and parliament. The name "Holland" is used to refer informally to the whole of the country of the Netherlands., The Alps are the highest and most extensive mountain range system that lies entirely in Europe, stretching approximately across eight Alpine countries: Austria, France, Germany, Italy, Liechtenstein, Monaco, Slovenia, and Switzerland. The mountains were formed over tens of millions of years as the African and Eurasian tectonic plates collided. Extreme shortening caused by the event resulted in marine sedimentary rocks rising by thrusting and folding into high mountain peaks such as Mont Blanc and the Matterhorn. Mont Blanc spans the FrenchItalian border, and at is the highest mountain in the Alps. The Alpine region area contains about a hundred peaks higher than 4000 metres (just over 13,000 feet)., The Roman Empire (Koine and Medieval Greek:   , tr. ) was the post-Roman Republic period of the ancient Roman civilization, characterized by government headed by emperors and large territorial holdings around the Mediterranean Sea in Europe, Africa and Asia. The city of Rome was the largest city in the world BC AD, with Constantinople (New Rome) becoming the largest around 500 AD, and the Empire's populace grew to an estimated 50 to 90 million inhabitants (roughly 20% of the world's population at the time). The 500-year-old republic which preceded it was severely destabilized in a series of civil wars and political conflict, during which Julius Caesar was appointed as perpetual dictator and then assassinated in 44 BC. Civil wars and executions continued, culminating in the victory of Octavian, Caesar's adopted son, over Mark Antony and Cleopatra at the Battle of Actium in 31 BC and the annexation of Egypt. Octavian's power was then unassailable and in 27 BC the Roman Senate formally granted him overarching power and the new title "Augustus", effectively marking the end of the Roman Republic., The Alpine region of Switzerland, conventionally referred to as the Swiss Alps (, ), represents a major natural feature of the country and is, along with the Swiss Plateau and the Swiss portion of the Jura Mountains, one of its three main physiographic regions. The Swiss Alps extend over both the Western Alps and the Eastern Alps, encompassing an area sometimes called "Central Alps". While the northern ranges from the Bernese Alps to the Appenzell Alps are entirely in Switzerland, the southern ranges from the Mont Blanc massif to the Bernina massif are shared with other countries such as France, Italy, Austria and Liechtenstein., The Belgae (or ) were a large confederation of tribes living in northern Gaul, between the English Channel, the west bank of the Rhine, and northern bank of the river Seine, from at least the third century BC. They were discussed in depth by Julius Caesar in his account of his wars in Gaul. Some peoples in Britain were also called Belgae and O'Rahilly equated them with the Fir Bolg in Ireland. The Belgae gave their name to the Roman province of Gallia Belgica and, much later, to the modern country of Belgium., The Roman Republic was the era of ancient Roman civilization beginning with the overthrow of the Roman Kingdom, traditionally dated to 509 BC, and ending in 27 BC with the establishment of the Roman Empire. It was during this period that Rome's control expanded from the city's immediate surroundings to hegemony over the entire Mediterranean world., Cologne is the largest city in the German federal State of North Rhine-Westphalia and the fourth-largest city in Germany (after Berlin, Hamburg, and Munich). It is located within the Rhine-Ruhr metropolitan region, one of the major European metropolitan regions and the largest in Germany, with more than ten million inhabitants., Belgium , officially the Kingdom of Belgium, is a sovereign state in Western Europe bordered by France, the Netherlands, Germany, Luxembourg, and the North Sea. It is a small, densely populated country which covers an area of and has a population of about 11 million people. Straddling the cultural boundary between Germanic and Latin Europe, Belgium is home to two main linguistic groups: the Dutch-speaking, mostly Flemish community, which constitutes about 59% of the population, and the French-speaking, mostly Walloon population, which comprises 41% of all Belgians. Additionally, there is a small group of German-speakers who live in the East Cantons located around the High Fens area, and bordering Germany., The Rhineland is the name used for a loosely defined area of Western Germany along the Rhine River, chiefly its middle section., Ambiorix was, together with Cativolcus, prince of the Eburones, leader of a Belgic tribe of north-eastern Gaul (Gallia Belgica), where modern Belgium is located. In the nineteenth century Ambiorix became a Belgian national hero because of his resistance against Julius Caesar, as written in Caesar's "Commentarii de Bello Gallico"., The Eburones (Greek: , Strabo), were, supposedly, a germanic tribe who lived in the northeast of Gaul, in what is now the southern Netherlands, eastern Belgium, and the German Rhineland, in the period immediately before this region was conquered by Rome. Though living in Gaul, they were also described as being both Belgae, and Germani (for a discussion of these terms, see below)., The North Sea is a marginal sea of the Atlantic Ocean located between Great Britain, Scandinavia, Germany, the Netherlands, Belgium, and France. An epeiric (or "shelf") sea on the European continental shelf, it connects to the ocean through the English Channel in the south and the Norwegian Sea in the north. It is more than long and wide, with an area of around ., Cativolcus or Catuvolcus ( died 53 BC ) was king of half of the country of the Eburones , a people between the Meuse and Rhine rivers , united with Ambiorix , the other king , in the insurrection against the Romans in 54 BC ; but when Julius Caesar in the next year proceeded to devastate the territories of the Eburones , Cativolcus , who was advanced in age and unable to endure the labours of war and flight , poisoned himself , after imprecating curses upon Ambiorix ., The Rhine (, , ) is a European river that begins in the Swiss canton of Graubünden in the southeastern Swiss Alps, forms part of the 
Swiss-Austrian, Swiss-Liechtenstein, Swiss-German and then the Franco-German border, then flows through the Rhineland and eventually empties into the North Sea in the Netherlands. 
The largest city on the river Rhine is Cologne, Germany, with a population of more than 1,050,000 people. It is the second-longest river in Central and Western Europe (after the Danube), at about , with an average discharge of about ., Subject: cativolcus, Relation: country_of_citizenship, Options: (A) academic (B) austria (C) belgium (D) france (E) gallia aquitania (F) gaul (G) germanic peoples (H) germany (I) great britain (J) italy (K) liechtenstein (L) luxembourg (M) netherlands (N) politician (O) roman empire (P) roman republic (Q) slovenia (R) switzerland
Output: gaul