This was not a good time to be a Jew in the Russian Empire. Granted, it was never especially easy, but during this period it was particularly bad. While Jews, like others, were coming off of the chaos and tragedy of the First World War, only to be plunged into the further chaos and instability of the civil war, the Russian Civil War also took place not-too-long after the outbreak of a series of pogroms, the most famous of which was the Kishinev pogrom of 1903, but which also included mass anti-Jewish violence that broke out in 1905 during the Russian Revolution. Hundreds of thousands of Jews were immigrating each year, mostly to the United States, so shtetl life was weakening and undergoing massive changes as its population was murdered, leaving, or experiencing deep trauma.
At the same time, the Russian Revolution (I know this is not the Russian Civil War. We’ll get there) was a major factor in activating the political consciousness of Jews throughout the Russian Empire, and not just in the big cities (that is, the cities they were permitted to live in). Tsar Nicholas was very antisemitic, so while different Jews in different areas aligned with different movements, these movements were all essentially against the tsar. In 1904 both religious communities and secular activists were actively demanding civil equality for Jews. A wide swath of Jewish activists established the Union for the Attainment of Full Rights for the Jewish People of Russia in March 1905 and opened branches throughout the Pale of Settlement (the area where Jews were allowed to settle within the Russian Empire); these branches would play a role not only in advocating for Jewish cultural autonomy and equal rights, but also in connecting the more isolated shtetls with what was going on in the wider world and get them politically engaged. The Bund, a Marxist Yiddishist workers’ organization, which had been founded in Vilna at the end of the 19th century, became increasingly active and organized a number of self-defense groups for Jews to fight back during pogroms. Three new Jewish political parties were established during this time: Poaley Tsiyon (Jewish Social Democratic Party), the Zionist Socialist Party, and the Jewish Socialist Labor Party. Even the most religious became politically active; yeshiva students began staging demonstrations (some of which turned violent) against the government. Some in the government recognized the growing radicalism within the Jewish community and attempted to calm it by granting Jews at least some additional rights, or ease certain restrictions, but the tsar was unsupportive (to say the least), and so any changes that were made were few and limited.
With that background, let’s turn our attention to the Russian Civil War. At this point you have a Jewish population that has both suffered extreme outbursts of violence against them over the course of years,, and that has also become increasingly politically aware and radicalized, regardless of where they lived and their level of religiosity, and they are increasingly unafraid to organize self-defense units against pogroms, oppose the tsar, and insist on their rights.
With the outbreak of the Civil War, Jews were, surprise surprise, the victims of pogroms. These pogroms were carried out by all of the major “sides” in the war, though to varying extents. The worst of the anti-Jewish violence was perpetrated by Ukrainian troops fighting for Ukrainian independence under the leadership of Symon Petliura (Petliura would eventually be killed by a Jew from Bessarabia in 1926 in revenge for the pogroms). So while some Jewish people were originally sympathetic to the Ukrainian struggle for independence, they were quickly alienated and disillusioned. While the White Army was responsible for fewer pogroms, they were perhaps the most openly antisemitic, and had the most active anti-Jewish propoganda (they associated Jews with communists).* Meanwhile, the Red Army had received specific instructions not to attack Jewish communities; while there were pogroms instigated by the Red Army they were far fewer and less deadly. I know that “they killed the least number of us” is damning with faint praise, but since they knew how much worse things could be, this was seen as promising. As a result, Jews increasingly began to support the Red Army, to the extent that there was a special commission that was set up to deal with the numbers of Jews wishing to join the Red Army’s ranks.
Bottom line: by the time that the Russian Civil War started, the average Yiddish-speaking Jew would have been at least politically aware, if not actively engaged. Compelled by an increased sense that they could be empowered to fight for their civil rights–and literally fight for their communities– it would not have been at all unusual for them to join the war effort against tsarist forces in some capacity. At the same time, it’s also important to point out that by this point a significant number of average Yiddish-speaking shtetl Jews were either dead or across the ocean, thereby taking themselves out of the entire situation.
The specific song that you mentioned, “Daloy politsey,” was probably collected in 1905, during the Russian Revolution when Jews were becoming increasingly politically conscious and radicalized. And it is a daringly radical song. Take this sample of the lyrics: “Brothers and sisters, let’s forgo formalities,/Let’s shorten little Nikolai’s years!...Cossacks and gendarmes,/Get down off your horses!/The Russian tsar is already dead and buried! (Brider un shvester, lomir zikh nit irtsn,/lomir Nikolaykelen di yorelekh farkirtsn…Kozakn, zhandarmen, arop fun di ferd!/Der rusisher keyser ligt shotn in der’erd)” It’s a song that is full of contempt for Nicholas, as well as explicit threats and calls to unite to bring Nicholas down. I don’t know if your average Yiddish-speaking Jew in the shtetl would have sung this particular song, but it does point to an increased sense of daring when it came to dealing with the authorities. It is a more radical version of sentiments that were already circulating and being expressed by your typical Yiddish-speaking shtetl Jews, but also one that was ultimately put into practice by those typical Yiddish-speaking shtetl Jews when the Russian Civil War broke out.
*(Also important to note is that a significant number of pogroms were “independently organized:” that is, people simply taking advantage of the chaos to engage in violence. But this isn’t a political movement, so I don’t think it’s worth more than a parenthetical.)