Short answers, pulled from the story.
Ancient Rome was the Roman civilisation that ran from the founding of the city in the 8th century BC to the collapse of the Western Roman Empire in the 5th century AD. It is divided into the Roman Kingdom from 753 to 509 BC, the Roman Republic from 509 to 27 BC, and the Roman Empire from 27 BC to 476 AD. Rome held independence for 1200 years and was a great power for nearly 700 years.
The Roman antiquarian Marcus Terentius Varro placed the city's foundation at 753 BC. By legend the city was founded by Romulus, son of Mars, who killed his twin Remus after a dispute and named his settlement on the Palatine Hill Roma quadrata. A rival legend recorded by Dionysius of Halicarnassus traced Rome to the Trojan prince Aeneas.
The Roman Empire reached its greatest territorial extent under Trajan, covering around five million square kilometres in AD 117. It held an estimated 50 to 90 million inhabitants, roughly 20 percent of the world's population at the time. It controlled the North African coast, Egypt, Southern Europe, most of Western Europe, the Balkans, and much of the Middle East.
The Republic was destabilised by generals who turned their armies against Rome, beginning with Marius and Sulla, who marched his legions into the city in 88 BC. Julius Caesar crossed the Rubicon in 49 BC and made himself dictator, and after his murder Octavian defeated his rivals and took the name Augustus in 27 BC. Historians mark that year as the beginning of the Roman Empire.
The five good emperors were Nerva, Trajan, Hadrian, Antoninus Pius, and Marcus Aurelius, who ruled within the Nerva-Antonine dynasty from 96 to 192 AD. Under Trajan the Empire reached its greatest extent, and Marcus Aurelius, known as the Philosopher, wrote the Meditations. The historian Gibbon called their rule the golden era of the Empire.
The Western Roman Empire fell in 476, when the chieftain Odoacer deposed the emperor Romulus Augustus, an event that usually marks the end of Classical antiquity and the start of the Middle Ages. The collapse followed the sack of Rome by the Visigoths in 410 and the loss of North Africa, Gaul, and Britannia. The Eastern Roman Empire survived almost 1000 years more, ending when Mehmed the Conqueror took Constantinople on the 29th of May 1453.