After the ending of the last ice age about 11,000 years ago humans moved throughout Europe. Various civilisations rose and fell with temples in Gobleki Tepi in Turkey detailing the zodiac 11,000 years ago, the Sumerian civilisation in Iraq with its writings about Noah and his ark 6,000 years ago, and the Egyptians 5,000 years ago. At this time in Scotland they were building Skara Brae, before the pyramids or Stonehenge. Then the Minoan culture evolved ( among others) followed by the Greeks and the tales of Troy. Greek colonies were established across the Mediterranean. In 753 BC, according to the Romans , Rome was founded.
The Romans were originally outcasts …Sabine women…Etruscans. expansion…Phoenicians naval battles…carthage….sacking of Rome by Gaul’s creation of Roman army. Wiliness to take others ideas….learn from mistakes.
Technology writing knowledge sharing. Roads, water, health, laws, slaves gaining freedom after 25 years. Adoption of other gods, usage of stick and carrot with other peoples. Grain for army, navy for supply.
BY 100 BC they had added many territories
Need for emperors to prove military prowess.
Options – people in Scotland, or the well armed the empires nearby. Naval power could be deployed , natives charged naked with bravery.
You can find on Wikipedia The complete Timeline of Roman History