Oh, you were answering the question? I thought you were talking about your private life there for a minute. Not that there's anything wrong with that of course.
Mmmm...sort of. As the city became a major trade port and commercial hub the rural peasants moved en masse into the city; same as in England as the Industrial Revolution began. And the immigration you mention started long before the Gauls and Germanic tribes. Very early in the republic's history Rome fought and defeated all her rivals on the Italian peninsular; the Samnites, the Latins etc. Many of these became subject cities, most with near full autonomy(for good behaviour) and at an early stage Roman citizenship was extended to much of the Italian peninsular. The Carthaginians were driven out of Sicily then annihilated. The Greeks were subjugated and huge numbers of Greek aristocratic slaves were taken and used as teachers for Roman patrician children, librarians, architects etc.
Dependent upon grain from Egypt and the shores of the Black Sea yes.
Yes, this was one of the big ones. Rome acquired a vast empire virtually overnight and was totally unequipped to maintain it. The legions were in constant battle putting down rebellions across the empire virtually continuously for over a hundred and fifty years. Gradually the patrician class started to forego their military service via a system where they could pay someone else to take their place in the legion. So the patrician class got soft and power transferred to the commoners who dominated the military. The empowered Tribunate was a threat to the Senatorial class and the city desperately needed fresh soldiers so "barbarians" were increasingly filled in the legions. These Germanic and Gaullic warriors were tougher than the now soft and debauched Romans and as you mention below they gained considerable power. In fact, Rome was a multiethnic society by the end of the republic. By the third century they had an Illyrian Emperor, then a German Emperor and even an Asyyrian Emperor.
Rome also had a large Jewish population and a large number of Roman converts and "God-fearers". Judaism became a very popular religion with the upper classes in Rome and at its peak before the Jewish revolts, 20% of the population of Rome were Jewish. If Paul and co. hadn't come along we might all be Hymies.
Even Emperor. Yes, by the fourth century Rome had their very own undocumented sovereign just like Obama.
Not the dole exactly. Socialism and handouts for sure. It took the form of grain handouts, land confiscation from the Senators distributed to the poor and to veterans of the legions. There were also the chariot races and the gladiatorial games. These were often paid for by candidates for office and they would often spend exorbitant amounts of money on buying votes with extravagant games and festivals. One thing they'd do is hand out ceramic bowls of food and the candidate would have his name inscribed into the bowl so people knew who paid for it and who they should vote for. I've seen one in a museum that was made by Cataline shortly before his ill fated coup.
Afraid not. In fact, Rome never actually had a police force. For a few centuries they had "vigiles" - firefighters who also acted as night watchmen and patrolled the streets at night. But they weren't really "police" and they were pretty ineffective. The real power in the city was the Praetorian Guard and by the third century the vigiles were disbanded. The Romans didn't rely upon public prosecutors to bring charges against someone. Citizens would bring charges directly against the accused and a jury trial of sorts heard and ruled on the case.
Yes, a long tradition of political assassinations, intrigue, coups and attempted coups etc.
I always liked the story of Caligula suddenly ordering the entire front row of spectators in the Colosseum to be seized and thrown into the ring to fight each other to death while the Emperor watched with glee.
They'd been ripe for a plucking for a long time. The fall of Rome resonated throughout the Empire as they withdrew the legions and left the locals to fend for themselves. When the legions pulled out of Britain they were immediately invaded by Germanic tribes and there's a famous letter one of the Gaulic Kings in England begging the Romans to return as they were being wiped out. Although it's regarded as very historically dubious, Geoffrey Monmouth's Historium Regum Britanniae gives a very interesting account that may very well be accurate despite the inaccuracies elsewhere in the work. A snippet if you're interested:
Rome had already died long before Alaric came to town. By the fifth century, Rome wasn't even the most important city in Italy. The patricians all fled to Ravenna, Alexandria, Byzantium and elsewhere throughout the crumbling Empire. Gibbon was keen to stress however, that it wasn't a sudden fall but rather a slow and inexorable decline over many generations. Gibbon blamed Christianity for the Romans becoming "soft".