The Lex Oppia was a law established in ancient Rome in 215 BC, at the height of the Second Punic War during the days of national catastrophe after the Battle of Cannae.
The Battle of Cannae was a battle that took place in 1018 between the Byzantines under the Catepan of Italy Basil Boioannes and the Lombards under Melus of Bari.
 The Lombards had also hired some Norman cavalry mercenaries under their leader Gilbert Buatère, while Boioannes had a detachment of elite Varangian Guard sent to him at his request to combat the Normans.
The second battle of Herdonia took place in 210 BC during the Second Punic War.
 Hannibal, leader of the Carthaginians, who had invaded Italy eight years earlier, encircled and destroyed a Roman army which was operating against his allies in Apulia.
 The heavy defeat increased the war’s burden on Rome and, piled on previous military disasters (such as Lake Trasimene, Cannae and others), aggravated the relations with her exhausted Italian allies.
 For Hannibal the battle was a tactical success, but did not halt for long the Roman advance.
 Within the next three years the Romans reconquered most of the territories and cities lost at the beginning of the war and pushed the Carthaginian general to the southwestern end of the Apennine peninsula.
 The battle was the last Carthaginian victory of the war; all battles which followed were either inconclusive or Roman victories.
The Battle of Austerlitz (2 December 1805/11 Frimaire An XIV FRC), also known as the Battle of the Three Emperors, was one of the most important and decisive engagements of the Napoleonic Wars.
 In what is widely regarded as the greatest ever victory achieved by Napoleon, the "Grande Armée" of France defeated a larger Russian and Austrian army led by Tsar Alexander I and Holy Roman Emperor Francis II.
 The battle occurred near the town of Austerlitz in the Austrian Empire (modern-day Slavkov u Brna in the Czech Republic).
 Austerlitz brought the War of the Third Coalition to a rapid end, with the Treaty of Pressburg signed by the Austrians later in the month.
 The battle is often cited as a tactical masterpiece, in the same league as other historic engagements like Cannae or Arbela.
The Battle of Mantinea was fought in 207 BC between Sparta under the Tyrant Machanidas, as part of the Aetolian League, and the Achaean League whose forces were led by Philopoemen.
 Both sides were supplemented by mercenaries.
 It was the major land battle in Greece of the First Macedonian War, which had occurred due to Macedonian alliance with Carthage in the aftermath of Hannibal's victory at the Battle of Cannae in the Second Punic War.
The Battle of Beneventum was fought in 214 BC near modern Benevento during the Second Punic War.
 Roman legions under Tiberius Sempronius Gracchus defeated Hanno's Carthaginian forces, denying Hannibal reinforcements.
 Livy gives a brief description of the battle, which was part of the Roman campaign to subdue the southern Italian city-states that had joined Hannibal after the Battle of Cannae.
The Battle of Cannae ( or ) was a major battle of the Second Punic War that took place on 2 August 216 BC in Apulia, in southeast Italy.
 The army of Carthage, under Hannibal, surrounded and decisively defeated a larger army of the Roman Republic under the consuls Lucius Aemilius Paullus and Gaius Terentius Varro.
 It is regarded both as one of the greatest tactical feats in military history and as one of the worst defeats in Roman history.
The term decisive victory refers to a military victory in battle that definitively resolves the objective being fought over, ending one stage of the conflict and beginning another stage.
 Until a decisive victory is achieved, conflict over the competing objectives will continue.
 Like all concepts of warfare, a decisive battle can take place from the tactical or unit level (Pavlov's House during the Battle of Stalingrad or the Chew House at the Battle of Germantown), the operational level (the Battle of Cowpens or the Battle of Cannae), all the way up to the strategic level (the Battle of Saratoga) or battles that bring an end to hostilities, such as the Battle of Hastings, or the Battle of Waterloo.
Gaius Terentius Varro ( ; fl.
 3rd century BC) was a Roman consul and commander.
 Along with his colleague, Lucius Aemilius Paullus, he commanded at the Battle of Cannae in 216 BC, during the Second Punic War, against the Carthaginian general Hannibal.
 The battle resulted in a decisive Roman defeat and his colleague Paulus's death and he was completely discredited by everyone upon returning to Rome due to his leadership and took no further part of the war.
The Battle of Montemaggiore (or Monte Maggiore) was fought on 4 May 1041, on the river Ofanto near Cannae in Byzantine Italy, between Lombard-Norman rebel forces and the Byzantine Empire.
 The Norman William Iron Arm led the offence, which was part of a greater revolt, against Michael Dokeianos, the Byzantine Catepan of Italy.
 Suffering heavy losses in the battle, the Byzantines were eventually defeated, and the remaining forces retreated to Bari.
 Dokeianos was replaced and transferred to Sicily as a result of the battle.
 The victory provided the Normans with increasing amounts of resources, as well as a renewed surge of knights joining the rebellion.

Question: What is Lex Oppia connection to Battle of Cannae?
Answer: law established