Two of his arguments cut against what most readers wanted shamanism to be.
The first concerns the shaman's condition. Nineteenth century and early twentieth century writers had generally read the shamanic crisis as pathology, an arctic hysteria or a seizure dressed up. Shirokogorov replied that the shaman is the person who handles the psychic disturbance of others: the institution exists because a population under stress produces disturbance, and the shaman is the socially sanctioned mechanism for absorbing and discharging it. On that reading the practitioner is not the sick member of the group but the one who keeps the group from being sick, and the states involved are trained rather than merely suffered.
The second concerns origins. The Tungus complex was widely taken to be archaic, a survival of something very old that had escaped the world religions. Shirokogorov argued the opposite for much of it: that the hierarchy of spirits, several of the ritual objects and a good deal of the terminology showed the impress of Buddhist and Chinese contact by way of the Manchus and the Mongols, and that what looked primordial was in significant part recent. That claim has been contested ever since, but it introduced a historical dimension the earlier literature lacked, and it is one reason his book is still argued with rather than merely cited.
He left Russia after the revolution, taught at Shanghai and then in Beijing, and died there in 1939.