Return of the Exiles
Religious Jews began returning to Israel from Poland in small groups in the late 1700s, with the purpose of preparing the Land of Israel for the final redemption. Most were students of Rabbi Eliyahu of Vilna and Rabbi Dov Ber of Mezritch.
From the late 1800s until 1914 (the beginning of World War I) the Jews returning from Poland were motivated to escape the bloody pogroms and wars in Eastern Europe and by the Zionist ideals of farming, building, and settling the Holy Land.
The Zionist-inspired Aliyah from Poland resumed after World War One up until 1939, the beginning of World War Two. Tens of thousands of Jews came from Poland during that time, broadening agricultural development in the Land.
The last wave of Aliyah from Poland came after World War Two, comprised of Holocaust survivors and war refugees.
Interestingly, Poland was the only country in the post-war Eastern Bloc (USSR allies) that allowed Jews to leave for pre-state Israel without visas or exit permits.