This documentary details the Nordic Bronze Age that existed in a time period between 1,800 BC—500 BC, also explaining how previously sheep herding people from the Eastern Steppes infiltrated the European continent starting in 3,500 BC, bringing their language, horses, and technology such as wheels and bronze metallurgy. It explains how people in mainland Europe became relatively advanced even before being subjugated by the Romans.
[Note: This is another interesting European history documentary that is one of my favorites. It is a good precursor to watching the “Barbarians II” documentary series that I posted here the other day.
Also the description that I initially wrote on its video page on the “History of the World in Videos” article was not accurate enough, so I have updated it to be as above.]