Khabarovsk is not Siberia but Manchuria. A highly contested region between Chinese, Mongols, Koreans and Japanese and since 19 century - Russians.
Japanese claim the land as the birth place of their nation, the same do Koreans. All nations teach their kids in school that this is their ancestral lands. The last conflict between Russians and Chinese over this land was in the 1960s.
In 2004 Putin for some reason cut away a few dozen square kilometers of the land near Khabarovsk and gave it to China back. Nowadays a lot of Chinese nationals live in the city. The region was like a wild wild west, but instead of cowboys, Ukrainian Cossacks settled it. Zub's ancestry is probably from that rough cut of people. They had to deal with Siberian tigers, wild bears, wolves and everything in between. Local aboriginal tribes are great hunters.
Dersu Uzala - Wikipedia One of them is immortalized by the greatest Japanese film director Akira Kurosawa.