Historians divide Polish migration to the United States into four distinct waves.
The first wave of immigration occurred in the early-to-mid 1800s, when approximately two thousand Polish intellectuals and nobles moved to the U.S. The second wave, which lasted until WWI and was made up primarily of laborers, was significantly different. The influx of 2.5 million predominantly Catholic Poles settling in the United States led to conflict with protestant Americans. In The Hundred Dresses, Wanda Petronski's father Jan would have come to America during this wave of migration.
Government-imposed immigration quotas hampered the third wave of immigration. Nonetheless, an estimated half a million Polish people, having been made refugees by war and political oppression in Europe, moved to the United States by the fall of communism in the late 1980s.
The current wave of migration mostly comprises young people who have grown up in post-Cold War era Poland, when Poland was under the control of the Soviet Union. This wave of migrants have sought to escape political and economic turbulence. According to census data, the vast majority of Polish-born Americans live in urban areas.