Marne River in the context of "Charenton-le-Pont"

Gallia Belgica ("Belgic Gaul") was a province of the Roman Empire located in the north-eastern part of Roman Gaul, in what is today primarily northern France, Belgium, and Luxembourg, along with parts of the Netherlands and Germany.

Before the Roman province came into existence in about 50 BC, the region was conquered by Julius Caesar during his Gallic Wars. His report, the Commentarii de Bello Gallico, described Belgic Gaul as one of the three parts of Gaul (Tres Galliæ), the other two being Gallia Aquitania and Gallia Lugdunensis. Belgica stretched from the Marne and Seine rivers, which Caesar described as a cultural boundary between the Belgae and the Celtic Gauls. In the north and east it stretched all the way to the Rhine. The official Roman province of this name was later created by emperor Augustus in 22 BC, and named after the Belgae, as the largest tribal confederation in the area. However, it also included the territories of the Treveri, Mediomatrici, Leuci, Sequani, and others who Caesar did not explicitly designate as Belgic.

The First Battle of the Marne or known in France as the Miracle on the Marne (French: miracle de la Marne) was a battle of the First World War fought from 5 to 12 September 1914. The German army invaded France with a plan for winning the war in 40 days by occupying Paris and destroying the French and British armies. The Germans had initial successes in August. They were victorious in the Battles of Mons and the Frontiers and overran a large area of northern France and Belgium. In what is called the Great Retreat the Germans pursued the retreating French and British forces more than 250 km (160 mi) southwards. The French and British halted their retreat in the Marne River valley, while the Germans advanced to 40 km (25 miles) from Paris.

With the battlefield reverses of August, Field Marshal John French, commander of the British Expeditionary Force (BEF), lost faith in the French and began to plan for a British retreat to port cities on the English Channel for an evacuation to Britain. Joseph Joffre, the French commander, maintained good order in his retreating army and was able to reinforce it with troops from his eastern flank and by integrating military reserve units into the regular army. By early September, the Franco–British forces outnumbered the Germans, who were exhausted after a month-long campaign, had outrun their supply lines and were suffering shortages. On 3 September, the military governor of Paris, Joseph Gallieni, perceived that the German right flank was vulnerable and positioned his forces to attack.

The Great Retreat (French: Grande Retraite) also known as the retreat from Mons, took place in the First World War. The retreat was more than 200 km (120 mi), from Belgium to the River Marne in France in August and September 1914. The French Fifth Army and the British Expeditionary Force had been defeated by the armies of the German Empire at the Battle of Charleroi (21 August) and the Battle of Mons (23 August). A counter-offensive by the Fifth Army, with some assistance from the BEF, at the First Battle of Guise (Battle of St. Quentin, 29–30 August) failed to halt the German advance. The retreat of the Fifth Army and the BEF continued to the south side of the Marne River. From 5 to 12 September, the First Battle of the Marne ended the Allied retreat and forced the German armies to retire towards the Aisne River and to fight the First Battle of the Aisne (13–28 September). Reciprocal attempts to outflank the opposing armies to the north known as the Race to the Sea followed from 17 September to 17 October.