A few Slovaks immigrated to the United States before the American Civil War but their numbers were small. Large-scale Slovak immigration to the United States began in the late 1870s, steadily increased during the following two decades, and peaked in 1905 when 52,368 Slovaks entered. Slovak immigration declined precipitously during World War I and started up again after hostilities ended in 1918. The movement came almost to a complete halt in the 1920s when American immigration laws virtually stopped East European immigration into the United States. According to immigration records 480,201 Slovaks entered the country between 1899 and 1918. The 1920 census found that there were 274,948 foreign-born Slovaks in the United States. Slovak immigrants and their children totaled 619,866.
Statistics on Slovak immigration, however, are imprecise, and it is difficult to determine the number that actually immigrated to the United States. Before 1899 U.S. immigration officials listed immigrants by country of birth. Thus, until 1899 Slovaks were recorded as Hungarians. Even after immigrants were enumerated by nationality, the Magyarization policies had been so effective that many Slovaks did not identify themselves as such. Also, perhaps one-third of the Slovaks who came to the United States were not immigrants but instead migrants. Often called "birds of passage," they worked temporarily in America and then returned to Europe. They wanted to earn money to buy property in their homeland. It was common for Slovaks to make several trips between the United States and Upper Hungary. At least 19 percent of the Slovaks who entered an American port from 1899 to 1910 had been in the United States one or more times before. Not until 1908 did immigration officials subtract the number of immigrants leaving from the total numbers entering the United States. Still, it is clear that temporary migrants formed an especially large contingent of the early stages of the Slovak immigration and remained a common feature of the movement. Between 1908 and 1910, for example, 80,797 Slovaks entered the United States while 41,726 left. Its temporary nature also affected the composition of the Slovak immigration. Most Slovak immigrants were unskilled laborers, and men typically outnumbered women by more than two to one. Between 1899 and 1910, 266,262 Slovak males and 111,265 Slovak females entered the United States.
Over time, many birds of passage decided to stay in America and sent for their families. The reasons for staying varied. Some were unable to save enough money to buy land and in some regions of their homeland no land was available. Others decided that America promised a better future while others married and decided to stay. Whatever their motives, between 1880 and the mid-1920s probably between 450,000 and 500,000 Slovaks moved permanently to the United States.
Slovak immigrants were committed to saving money and fulfilling obligations to families left behind. As a result they routinely sent money to Europe. In 1899 alone more than $4 million was channeled to the Slovak region of Hungary. The determination to save money, compounded by the fact that so many Slovaks were males who had come alone, influenced living standards. In general, Slovaks tried to live cheaply. Laborers often roomed in boardinghouses where they could get a bed and daily meals for as little as ten dollars per month. These boardinghouses were typically run by Slovak immigrants, a husband and wife who either owned or rented a large house. For these Slovak families, taking in boarders became an important source of additional income.
Slovak immigration began during a period when anti-foreign sentiment was on the rise in the United States. The response by Americans to Slovaks reflected the common anti-foreign attitude. Furthermore, the desire by Slovaks to live cheaply, the large number of males, and their concentration in unskilled industrial jobs reinforced beliefs that immigrants were creating social and economic problems for the United States. Slovaks were not usually singled out as presenting special problems. Since Slovaks did not have a separate identifiable homeland and most Americans did not know that there was a Slovak people, they often referred to Slovak immigrants simply as Slavs, Slavic, Slavish, or by the pejorative terms Hunky or Bohunk. Based on their geographic origin, Slovaks fell into the general category of undesirable immigrants. Judging persons from both eastern and southern Europe as biologically and intellectually inferior and a threat to American society, some native-born Americans demanded that these "undesirables" be barred from the country. The immigration laws of the 1920s that curtailed southern and east European immigration severely reduced the number of Slovaks who could enter the United States. Between 1929 and 1965 American quotas permitted only 2,874 persons from Czechoslovakia to immigrate annually to the United States. In the decades after immigration restriction went into effect, Slovaks were lost in popular perceptions and culture, as they were lumped into generalizations about the massive turn-of-the-century immigration.
Slovak Americans rank as the second largest Slavic group in the United States. The 1990 census revealed that 1,882,897 Americans claimed Slovak descent: 1,210,652 listed Slovak as their "first ancestry," and another 672,245 designated it as "second." Nearly three-fourths (74.7 percent) of Americans acknowledging some Slovak descent resided in the Northeast and Midwest. Less than .03 percent of the 1990 Slovak American population was foreign born, and 74 percent of these immigrants had come before World War II.