A couple of months ago I wrote about The Russian Language in the Twentieth Century by Comrie, Stone, and Polinsky; I’ve continued working through it, and I thought I’d pass on this interesting bit from the chapter on morphology:
Analyticity in the Nominal Paradigm
The most distinctive feature of grammatical change in the twentieth century has been the growth of analyticity—the increasing tendency for the grammatical meaning of words to be expressed by their context rather than their form and for the expression of separate meanings by separate words that can be used on their own, in isolation. An obvious aspect of this tendency is the growth of indeclinability among nouns. With the increase in the number of indeclinable nouns in the twentieth century growing account has to be taken of them in describing the morphological system….
Some [indeclinables], but not many, were borrowed as long ago as the eighteenth century, including депо [depo ‘depot’] and бюро [byuro ‘bureau’]. The habit of not declining them grew up in the first half of the nineteenth century among the upper class, but declined forms too, such as на бюре, на фортепиане are attested from that period… Only certain members of the intelligentsia and upper class, owing to their knowledge of Western languages, were conscious of the foreign origin of these words, and it was only in upper-class circles that they were not declined….
The vast majority of the population were ignorant of the Western languages from which these words came, and, on the rare occasions when they knew and used such words, they declined them. At the time of the Revolution non-declension of neuter loan-words had acquired prestige among the ruling class, but to the illiterate masses it was unknown or (if known) incomprehensible. It would therefore have been quite possible in the early years of Soviet power to codify declension of these words as standard, approximating Russian practice to that of most other Slavonic languages. Only a small minority of the population would have been offended.
After 1917, however, non-declension continued its progress under the impetus of the pre-Revolutionary prestige structure. And so, when in the 1960s, as part of the RJaSO [Русский язык и советское общество] project, a survey was carried out in which 1500 Russians were asked: ‘Do you accept the possibility of declining … nouns … of the type пальто, депо?’ only 3 per cent said ‘Yes’. The actual text of the replies received indicates that most of the informants were quite indignant at the thought of declining them.
So non-declension, like classical music, was an upper-class preference continued by the Soviets.