The politics of the Second Polish Republic were often quite confusing. Shifting political alliances, autocratic coups, and new political parties created an environment that was in a state of flux. The Sanacja's fusion of the right and canter-right and center-left parties may have created some stability within central government, but at the cost of alienating those left out of the ruling government. But there was one constant in interwar Polish politics: a widespread consensus favoring Polish ethno-nationalism. What this meant for Poland's ethnic minorities, which accounted for around 35% of the population, was most Polish political parties did not accept minority rights and were hostile to notions of civil equality.

Even though Poland had modeled its constitution on that of the French Third Republic and Piłsudski entertained notions of creating a Poland that was more akin to the departed Commonwealth, albeit one run by Poles, the Second Republic was no friend to its ethnic minorities. The various governments' towards Poland's Ukrainians and Belorussians was a curious successor to the Romanov's policies towards these groups in the nineteenth century. Instead of seeing them as national minorities, a good many Polish ethno-nationalists in the central government saw these ethnicities as "lost" Poles who would be brought back into the Polish fold through state intervention. Like the Russians, the Second Republic closed down schools and churches while treating Ukrainian or Belorussian resistance to these initiatives as the result of foreign interference. The state was a little more lenient towards German minorities in Posnan and the Masurian regions by virtue of the fact that they possessed a powerful patron in the form of Germany and this minority itself was a rather wealthy one compared to their neighbors. Most political opinion held that Germans were unassimilatable, but believed there was little to do about the situation.

The state and political parties' attitude Jewish minority in Poland fused the worst elements of this attitude to minorities. On one hand, one of the common points of political consensus by Polish politicians and intellectuals was that Jews, like the Germans, were fundamentally incapable of Polonization. Even among educated Catholic conservatives, there was a feeling that Jewish converts were insincere and a potential source for polluting the Polish catholic body politics. Yet, simultaneous to this exclusion of Poles, there was a marked distaste for accepting any sign of independent Jewish associational life or other participation within Polish state and society. As with Ukrainians and Belorussians, a number of Poles saw Jewish activism as a foreign import, in this case, often from the USSR. Żydokomuna (Jewish Communism) became one of the more common conspiracy theories within the Second Republic and the notion that Jews were in control of Moscow was not an uncommon one. Nor was this antisemitism confined to paper. The wave of pogroms of 1935-37 showed not only a popular support for antisemitism, but also state indifference to the civil rights of its Jewish citizens/subjects.

The solution the Republics' governments pushed was for the emigration of the nation's Jews from Poland. The calls for emigration increased with the Depression as a number of Polish antisemites blamed Jews as a drain on the economy, but a push for emigration as a solution was common in the 1920s as well. This made for some strange political bedfellows among the Polish Jewish community. Roughly speaking, the two dominant strains of Polish Jews from the prewar period that carried through the Republic were Zionism and Bundism. The latter was a more secular orientated trade unionism heavily influenced by Austromarxism and notions of Bauer's national-cultural autonomy. Zionism was likewise secular, but increasingly felt that Jews needed to find a homeland outside of Europe. One of the appeals of Zionism for Russian Jews during the Partition period was its militant line on self-defense and communal organization. The stridency of these Jewish political grouping grew with independence, even though a solid majority of Polish Jews preferred to stay uninvolved with politics.

The most prominent champions of emigration made a tactical alliance with the Zionists in the 1930s. The Polish government made overtures to its French ally, for example, to open up the island of Madagascar for Jewish emigration. But most of the emigration advocates saw Palestine as the best hope for resolving the Polish question. Warsaw pushed London to open up emigration quotas to Palestine and sent some arms and provided training to what later became the Zionist militia in Palestine, the Haganah. The Republic's attitude on Palestine was a marked contrast to the antisemitic policies of Nazi Germany, which pushed for emigration as a solution but drew the line at open support for a Jewish state.

But Zionism was a minority position among Polish Jewry. Bundists too were also a minority, but did have some alliances and contacts with the Polish left. Although the Polska Partia Socjalistyczna (Polish Socialist Party/PPS) was part of the opposition to Sanacja, it was one of the more forceful champions of minority rights within Poland. Polish communists too also pushed for minority rights, albeit they were much more focused on Ukrainian and Belorussian rights than Jewish ones. But the PPS's Jewish policies tended to be more about toleration and limited civil equality than assimilation or even going the step and considering Jews to be Poles regardless of religious identification. Much of the PPS's rank and file held the same prejudices as their conservative and center rivals and attacks on antisemitism by the PPS were less about defending Jews than pointing out the hypocrisies and retrograde thinking of Polish conservatives.

Thus any move for an internal Jewish nation inside Poland was a non-starter during the Republic. A broad strata of Polish politics already held that ceding non-Polish minorities rights was unthinkable for Poland even for groups that Polish political opinion felt could be Polonized over time. Bundist-style Austromarxist national-cultural autonomy was a step too far for some on the Polish left to stomach. Paradoxically, one of the emerging consensus points by the end of the 1930s within Polish politics (outside the left) was to treat Polish Jews as a separate nation as a means to encourage emigration. While a number of Poles might support this notion, the idea that a separate nation especially one composed of Jews, could exist inside the borders of Poland was anathema.

Sources

Melzer, Emanuel. No Way Out: The Politics of Polish Jewry 1935-1939. Cincinnati: Hebrew Union College Pr, 2015.

Michlic, Joanna B. Poland's Threatening Other: The Image of the Jew from 1880 to the Present. Lincoln, Neb: University of Nebraska Press, 2009.

Zimmerman, Joshua D. The Polish Underground and the Jews: 1939 - 1945. Cambridge: Cambridge Univ. Press, 2015.

The sort of Jewish nationalism popular during this period was really just Zionism. While there were areas with significant Jewish minorities and even Jewish majorities, they weren't exclusively Jewish or anything close, nor were they really continuous. A few cities were majority Jewish, but there were huge areas that were like a third Jewish, which doesn't make a good country. Plus there wasn't really a good ideological reason in favor of such a thing.

The closest thing to what you're describing is a political movement called Bundism. Bundism was a fairly popular ideology in pre-war Poland. It was a Jewish political movement, but a secular one. They were secular socialists who were proponents of Jewish identity and culture, most importantly use of Yiddish. While they may've wanted to continue some level of Jewish political autonomy, they did not support Zionism, nor were they interested in establishing a Jewish state in general. They were a fairly popular political group among Jews in Poland, along with religious political parties and Zionist ones.

The 1-2 punch of the Holocaust and the establishment of Israel (which was a resounding victory for the Zionist wing of Jewish politics) pretty effectively destroyed the political movement. But, some of their ideological descendants exist, especially among Yiddishists, but also among other left-wing Jewish organizations, in the US.