I was reading somewhere that, in certain Japanese temples, one can see Roman glassware. To be clear, Roman glassware that was purchased when it was new by the temple staff. It was a reminder that the Silk Road
was a real thing. So, not only was the road real, but at least some people on both ends of the road were aware of the people on the other end.
Think about that. Roman emperors were at least tangentially aware of Japanese emperors, and vice versa. But from a day-to-day perspective, they had no influence on each other.
Where this ties into space (no, I'm not obsessed about space, I can stop thinking about it any time I want to
) is in terms of alien civilizations. The best guess we have about intelligent life in the galaxy is that we would expect, on average, civilizations to be separated by about 200 light years. Now, averages are funny, and so you could have a civilization a thousand light years from its nearest neighbor or one light year and still have an average galaxy-wide of 200 light years.
But 200 light years is a God-awfully long way. Travelling at the speed of light, a trip would take 200 years - assuming you can go that fast and don't need to stop for anything. Even travelling at 100 times the speed of light - or 100 times faster than Einstein says you can - that's a two-year trip one way.
This would, I suspect, set up something similar to the old Silk Road. Sufficiently-advanced civilizations would be aware of each other, and would probably have some low level of trade, but very little real influence on each other.
The universe is big, old and empty too.