Titus Livius or Livy (59 BCE - 17 CE): Roman historian, author of the authorized version of the history of the Roman republic.
A large part of Livy's History of Rome since the Foundation is now lost, but fortunately we have an excerpt, called the Periochae, which helps us reconstruct the general scope. This translation was made by Jona Lendering.
From Book 21
[21.1] Itnote[Book 21.] tells about the beginning of the Second Punic War, and how Hannibal, the Carthaginian leader, crossed the river Ebro and violated the treaty.
[21.2] [218 BCE] He besieged Saguntum, a Roman ally, and took it in the eighth month.
[21.3] Because of these violations, envoys were sent to the Carthaginians, to ask for an explanation.
[21.4] When they refused satisfaction, war was declared.
[21.5] Hannibal crossed the Pyrenees, traversed Gaul, defeated the Volcians (who tried to stop him), arrived at the Alps, had a difficult crossing of this mountain range, in which he several times had to rout Gallic mountain tribes, descended to Italy, and defeated the Romans in an equestrian battle near the river Ticinus.
[21.6] In this battle, Publius Cornelius Scipio was wounded but saved by his son, who later accepted the surnamed Africanus.
[21.7] Hannibal defeated a second Roman army near the river Trebia, and crossed the Apennines. Tempests caused great problems for the soldiers.
[21.8] In Hispania, Gnaeus Cornelius Scipio successfully fought against the Carthagians, and captured the leader of the enemies, Mago.
From Book 22
[22.1]  Losing much sleep in the marshes, Hannibal lost an eye, but he arrived in Etruria, having been marching without interruption through those marshes for four days and three nights.
[22.2] Consul Gaius Flaminius, a headstrong man, proceeded against the enemy, in spite of bad omens and although he had had to order the military standards, which could not be moved, to be dug out, and although the horse he had mounted had thrown him over the head. He was ambushed by Hannibal near the Trasimene lake, and massacred with his army.
[22.3] Six thousand men who had broken out were chained by the perfidity of Hannibal, although Atherbalnote[Real name Maharbal.] had given his word.
[22.4] There was general mourning because of this disaster, but two mothers died of joy when they discovered that their sons, who they believed to be dead, were still alive.
[22.5] Because of this disaster, on the authority of the Sibylline books, a Sacred Spring was decreed.
[22.6] Dictator Quintus Fabius Maximus was sent out against Hannibal, but refused to offer battle because he did not want to force his already defeated soldiers to fight against the violence of victorious enemy, and was content to impede Hannibal's progress and block his way; but Marcus Minucius, his aggressive and headstrong master of horse, persuaded the people that his own powers should be equal to those of the dictator, whom he charged with sluggishness and timidity; on an unfavorable place, he offered battle with his part of the divided army, and his legions were in great danger, but were saved when Fabius Maximus arrived with his part of the army.
[22.7] After this happy outcome, Minucius joined camp with the dictator and saluted him as his father, ordering his soldiers to do the same.
[22.8] Hannibal laid waste Campania and was blocked by Fabius between the town of Casilinum and Mount Callicula, but Hannibal attached and lighted twigs on the horns of cows, which frightened the Roman garrison at Callicula. It fled and Hannibal marched over the pass.
[22.9] He also spared the land of dictator Quintus Fabius Maximus, although he burned the entire countryside, so that his opponent was suspected of treason.
[22.10]  After this, Aemilius Paullus and Terentius Varro became consul and under their leadership, a large defeat was suffered against Hannibal, at Cannae, in which forty-five thousand Romans were killed, including consul Paullus, ninety senators, and thirty former consuls, praetors, or aediles.
[22.11] Now, some desperate young noblemen were plotting to leave Italy, but military tribune Publius Cornelius Scipio (who was later called Africanus), held his drawn sword over their heads and announced that he would consider everyone an enemy who would not swear what he dictated, and forced them to promise never to abandon Italy.
[22.12] Because of manpower shortage, eight thousand slaves were armed.
[22.13] Prisoners of war were not bought free, although there was an opportunity.
[22.14] Itnote[Book 22.] also contains accounts of panic and grief in the city, and fights in Hispania with a successful outcome.
[22.15] Vestal virgins Opimia and Florentia were condemned for unchastity.
[22.16] People went out to greet and thank Varro, because he had not despaired about the state.
From Book 23
[23.1] [216 BCE] The Campanians sided with Hannibal.
[23.2] Mago was sent to Carthage to bring the news of the victory at Cannae. At the entrance of the Senate building, he poured out the golden rings taken from the bodies of those killed in action; it is said that there were a great many of them.
[23.3] After this news, a Carthaginian nobleman named Hanno, argued that the Carthaginian Senate should offer a peace treaty to the Roman people, but he was unsuccessful because the faction of the Barcids protested.
[23.4] At Nola, praetor [Marcus] Claudius Marcellus, made a sally against Hannibal, and was successful.
[23.5] Casilinum was besieged by the Carthaginians and the garrison suffered so much from hunger that they ate thongs, the hides that they had removed from their shields, and even mice.
[23.6] They survived on nuts that were sent down the Vulturnum by the Romans.
[23.7] The Senate was supplemented with hundred and seventeen new members of the equestrian order.
[23.8] Praetor Lucius Postumius and his army were killed by the Gauls.
[23.9] In Hispania, Gnaeus and Publius [Cornelius] Scipio defeated Hasdrubal and made Hispania theirs.
[23.10] The survivors of the army of Cannae were sent to Sicily, and were not to return before the end of the war.
[23.11] Consul Sempronius Gracchus defeated the Campanians.
[23.12] Praetor Claudius Marcellus routed and defeated the army of Hannibal near Nola, and gave the Romans, tired by so many defeats, a better hope for the war.
[23.13]  A treaty was concluded between king Philip of Macedonia and Hannibal.
[23.14] Itnote[Book 23.] also contains an account of successful fights against the Carthaginians in Hispania, waged by Publius [and Gnaeus Cornelius Scipio, and on Sardinia by] praetor Manlius. They captured general Hasdrubal, Mago, and Hanno.
[23.15] In its winter camps, Hannibal's army got so used to luxury, that it was weakened in mind and body.
From Book 24
[24.1] King Hieronymus of Syracuse, whose father Hiero had been a friend of the Roman people, defected to the Carthaginians and was murdered because of his cruelty and pride.
[24.2]  Proconsul Tiberius Sempronius Gracchus successfully fought against the Carthaginians and their leader Hanno near Beneventum, receiving great help from slaves, whom he ordered to be liberated.
[23.3] On Sicily, which had almost completely transferred its loyalty to the Carthaginians, consul [Marcus] Claudius Marcellus besieged Syracuse.
[24.4] War was declared against king Philip of Macedonia, who was surprised during a nocturnal battle at Apollonia and was forced to flee to Macedonia with an almost disarmed army.
[24.5] Praetor Marcus Valerius was sent out to wage this war.
[24.6]  Itnote[Book 24.] also contains an account of the war fought in Hispania against the Carthaginians by Publius and Gnaeus [Cornelius] Scipio.
[24.7] They received king Syphax of Numidia as friend. He had been defeated by king Massinissa of the Massylians, who fought for the Carthaginians, and had crossed, with a large army, to Scipio in Hispania near Gades, where Africa and Hispania are separated by a narrow strait.
[24.8] The Celtiberians were received as friends too.
[24.9] When their help had been invoked, for the first time, a Roman camp included mercenaries.
From Book 25
[25.1] Publius Cornelius Scipio, later called Africanus, was made aedile before he had reached the minimum age.
[25.2]  Aided by a group of young Tarentines who pretended to go out hunting during the night, Hannibal captured Tarentum, except for the citadel, to which the Roman garrison had escaped.
[25.3] The Games of Apollo were organized in accordance with the Oracles of Marcius, which had predicted the disaster at Cannae.
[25.4] Consuls Quintus Fulvius and Appius Claudius successfully fought against the Carthaginian leader Hanno.
[25.5] Proconsul Tiberius Sempronius Gracchus, led into an ambush by his host in Lucania, was killed by Mago.
[25.6] Centennius Paenula, who had served as a centurion, asked the Senate to give him an army and promissed a victory over Hannibal if he received it, received eight thousand soldiers, was made general, engaged Hannibal, and was slain with his army.
[25.7] Capua was besieged by consuls Quintus Fulvius and Appius Claudius.
[25.8] Praetor Gnaeus Fulvius unsuccessfully fought against Hannibal.
[25.9] Twenty thousand men were killed in action, but he himself escaped with two hundred cavalry.
[25.10] In the third year, [Marcus] Claudius Marcellus took Syracuse, and behaved himself as a great man.
[25.11] In the chaos of the captured city, Archimedes, concentrated on the figures he had drawn in the sand, was murdered.
[25.12] After many successes, Publius and Gnaeus [Cornelius] Scipio met with a sad end in the eighth year after their arrival in Hispania, when they were massacred with almost their entire army.
[25.13] Possession of that province would have been lost, had not the remnants of the armies been regrouped by the valor and energy of Lucius Marcius [Septimus], a Roman knight, who encouraged the soldiers and stormed two enemy camps.
[25.14] About twenty-seven thousand were killed; thousand and eighty men and an enormous booty were captured.
[25.15] Marcius was surnamed Dux, Leader.