Please note, that video supports my point: between 500BC and 1600BC, Russian language was non-existing. It's why video jumps from 500BC (proto-Slavic language)

Please note, that video supports my point: between 500BC and 1600BC, Russian language was non-existing. It's why video jumps from 500BC (proto-Slavic language) to 1400BC straight, skipping 1K years, 2/3 of history of Slavs.