Although the civic-ethnic binary is a tempting model for understanding the nature of citizenship and state identity, it often obscures the contradictory and quite ambiguous ways citizenship laws function. The case of Prussian Poland under the Kaiserreich exemplifies the difficulty in categorizing citizenship in a bifurcated manner. Although the German Empire was predicated as a German state, Poles made up an anomalous and largest minority within the Kaiserreich.

Ethnic Poles in Germany, whether in Prussian Poland, but also as migrant agricultural laborers (Sachsenganger) or industrial laborers in the Ruhr (the coalmines earned the nickname Ruhr-Polen in this period), were on paper citizens of Prussia, and thus by extension were imperial citizens who enjoyed the rights enshrined in the imperial constitution. Even though they were a minority on a national level, universal suffrage and Polish majorities in the three Prussian Polish provinces meant that Polish conservative politicians of the Polish Party (Koło Polski) could be a vital swing bloc in the Reichstag and the Prussian government. Additionally, Polish voters were also a vital element in the electoral successes of the Catholic Centre party and Silesia became one of the Centre's main strongholds. Bismarck and his successors viewed this emergence of a Polish voting bloc with considerable alarm and alternated between courting Koło Polski and other Polish factions and trying to minimize Polish civic rights within the country. The latter position gradually won out and the imperial state apparatus sought to minimize or remove Polish influence upon German politics. Newer historiography on the Kulturkampf has emphasized that many anti-Catholic policies continued on inside Prussian Poland after its 1887 "end" in southern and central Germany, with a much greater effort by the German state to break Polish voting blocs. There was also a concentrated effort to expel allegedly illegal Polish and Jewish tenants from Prussian Poland and Germanize the land through tax-incentives and other inducements for German settlers. The Prussian state also began a large-scale effort Germanize segments of the population by making German-language instruction mandatory in Prussian Poland. The central state's antipathy towards the Polish minority filtered down both into the bureaucracy and within German nationalist discourse, the latter of which often portrayed Poles as the antithesis of German virtues of thrift, level-headedness, and cleanliness. Best-selling novels like Soll und Haben emphasized the fundamentally alien nature of Poles and codified tropes of the simple, but dangerous Pole, in German culture. The anti-Polish stance of the state and segments of German society created an increasingly tense situation in both Prussian Poland and the Ruhr by the dawn of the twentieth century. Sometimes these tensions boiled over, such as during the 1906-07 school strikes in which a German teacher's beating of Polish students prompted major protests in West Prussia and Posen.

Older historiography has emphasized that the increasingly anti-Polish bent of the German state fostered an ethnic-based conception of citizenship that was fundamentally incompatible for any beneficial or enlightened rule over Poles. This line of analysis contends that the Polish-German antagonism evolved out of a procession of clear anti-Polish actions by Germans followed by Polish defensive reactions. German nationalism became acutely chauvinistic because acted in conjunction with a strong centralized state to create a society that excluded and oppressed Poles. The aggressiveness of German nationalism then hastened the crystallization of a latent national consciousness among a Polish minority that longed for national independence. However, recent scholarship on the German-Polish question has noted that the situation on the ground was much more complicated. For example, the largely Protestant-led Ministry of Education consistently favored funding German Protestant schools in Prussian Poland and often neglected schools whose student body was overwhelmingly Polish Catholic. In the Posen municipal district, 56 out 97 Protestant German schools had less than 20 pupils in 1906, while the neighboring Bromberg district, which was predominantly Polish Catholic, a 100:1 pupil-teacher ratio was the norm in this district’s 155 Catholic schools. Thus Polish odium over school policy in 1906-07 stemmed not just from cultural nationalism, but also a grievance from citizens of a state that had legally promised free and compulsory education. Moreover, a decade earlier, the Polish Fraktion in the Reichstag had actually wrung a concession from Caprivi a decade earlier that the state would not interfere in Polish-language instruction on Catholicism, a compromise that the Ministry of Education ignored in the run up to the 1906-07 strikes.

Despite the increasing antipathy towards the Polish minority, the Kaiserreich officials often had to operate within the preexisting civic structures of the German state. The 1885 expulsion and appropriation of Polish land had to operate on a largely fictional notion that its occupants were not legal occupants of Prussia. While the German state puts its thumb on the scales when interpreting existing German law as it applied to Poles, they could not eliminate these civic structures entirely. The state's 1885 expulsions were met with considerable vocal opposition within both the Reichstag and the German press. Polish communities and leaders proved occasionally quite adept at manipulating these structures in the face of anti-Polish laws and other forms of state discrimination. Nor was the definition of either German or Pole particularly clear-cut in this period. German discourses on Poles at times tended to differentiate between more neutral domestic Poles and "foreign" Poles from Galicia or Russian Poland who were allegedly more active agents of Polonization. Nor was the German approach to the Polish question monolithic. The liberal satirical newsweekly Simplicissimus assailed the government’s use of troops to quell the 1906-07 strikes, and its cartoon cover of its 26 November 1906 issue shows stereotypical East Elbian Junkers chasing Polish children back into the schoolhouse with the caption "Go back in there and learn German you band of Poles- just as we Prussians had to!" implying that the somehow Prussians' claim to Germanness was not purely authentic. There were also cleavages within the political Catholic milieu with German Centre delegates sometimes acquiescing to Germanization efforts on the grounds of civilizing their Polish co-religionists while Polish Centre officials resisted these measures.

These ambiguities should not obscure the fact though that the Kaiserreich's government increasingly took out an anti-Polish stance from the 1880s onward, but they often had to operate their ethnically-based exclusion of Poles via existing civic structures. Because of this, anti-Polish measures were often incompletely implemented and the continued existence of Poles as a political force, albeit a minority one, contributed to a growing climate of confrontation and conflict that characterized the Kaiserreich's political world in its last decades.

Sources

Conrad, Sebastian. Globalisation and the Nation in Imperial Germany. Cambridge: Cambridge University Press, 2010.

Kulczycki, John J. School Strikes in Prussian Poland, 1901-1907: The Struggle Over Bilingual Education. Boulder: East European Monographs, 1981.

-. The Polish Coal Miners’ Union and the German Labor Movement in the Ruhr, 1902-1934: National and Social Solidarity. Oxford: Berg, 1997.

Lamberti, Marjorie. State, Society, and the Elementary School in Imperial Germany. Oxford: Oxford University Press, 1989.

Liulevicius, Vejas Gabriel. The German Myth of the East. Oxford: Oxford University Press, 2009.

Trzeciakowski, Lech. The Kulturkampf in Prussian Poland. Translated by Katarzyna Kretowska New York: East European Monographs, 1990.

Just wanted to say thanks to the here! Agree it's a muddled question and both sides have points.

Anyone else want to jump in here?

The term "blood and soil" is used to describe 19th century German romantic nationalism that was rooted in a combination of descent (blood) and living on German territory (land). Given the land aspect, I can see how it's possible to make an argument for civic, since some of the children of polish parents who was born in Germany could still claim this attachment to German territory. On the other hand, the blood aspect remains. But the Kulturkampf was primarily a struggle against Catholicism, not ethnic differences, I believe. (Though ethnic Poles tended to be Catholic, it was as Catholics, not Poles, that they were being attacked.) And German-speakers and Germanic cultures were left outside the borders when Germany was founded (Austria, Switzerland). So... it was rooted in an uneasy marriage of ethnic and civic nationalism that eventually led to tensions...? (she concludes tentatively.) I am sure 19th century Germanists could jump in with a much more up-to-date knowledge of the current historiographical trends here.