Nikolai was born in the fishing village of Svetlojarsk, on the north-east of Chernarus. He was a normal Chernarussian young man who lived with his family until the beginning of the outbreak. At that moment he lost his family, his neighbors, friends, and everything that he had. His whole homeland changed like in a horror movie, and he was forced to flee away from his village, into the forest, where he learned to survive by eating mushrooms and berries, and avoided all contact with any other human, both healthy and infected.
Nikolai survived for three years hidden in the Chernarussian forest, but his life was going to change again 690 days after the beginning of the infection, when he stepped on a bear trap. This must have been placed by any of those foreigner dogs who had been invading his country, that's for sure. Nikolai was not able to escape from the trap, and stayed there for three days, bleeding and starving, waiting for his death.
Miraculously, he was saved by a man called Tony Montana, who found Nikolai and released him from the trap. During the following days Tony took care of Nikolai, whose wounds healed, but he is still not able to sprint long distances. Nikolai is extremely grateful to Tony and will do anything that Tony asks him to do.