Naturalization

DEFINITION: Process by which immigrants become citizens of the new countries in which they reside

SIGNIFICANCE:The naturalization process in the United States has offered citizenship to persons born in other countries, but the process itself has historically raised issues about fairness, national security concerns, and public perceptions of certain immigrant groups.

The issue of citizenship is so important that naturalization is mentioned within the foundation law of the United States, the US Constitution. Article I, section 8 of that document authorizes the US Congress to “establish an uniform Rule of Naturalization.” In 1790, the year after the Constitution was ratified, Congress enacted its first naturalization law. The Fourteenth Amendment, which was ratified in 1868, expanded the constitutional definition of citizenship. Since that time, additional legislation has continued to refine the legal rules concerning naturalization.

Early Years of the Republic

When the framers of the US Constitution considered the issue of naturalization, they decided that Congress should have the power to establish uniform laws and procedures governing the process by which citizens of other countries could become American citizens. Before the Constitution was ratified, naturalization procedures were conducted by the courts of individual states, but the members of the Constitutional Convention of 1787 decided that leaving such an important matter to the states would create confusion. They agreed that decisions concerning naturalization should be ruled upon only by courts with common law jurisdiction. It was also necessary for the procedures to be conducted with prothonotaries (court clerks) and official seals.

Congress’s passage of the Naturalization Act of 1790 created guidelines for US citizenship. In limiting citizenship to free White persons, the law denied the possibility of citizenship to indentured servants, free African Americans, Native Americans, and, later, Asians. The law also stated that White immigrants of “good moral character” could petition state courts for citizenship after they had been residents of the United States for two years and were residents of the states to which they made their petitions. Only five years later, that law was superseded by the Naturalization Act of January 29, 1795. The new law increased the period of residence from two to five years. It also mandated that immigrants wanting to become American citizens had formally to declare their intention to become citizens three years before they formally applied. New citizens were also required formally to renounce all allegiance to their former countries.

In 1798, Congress again increased the period of residence necessary to apply for citizenship, from five to fourteen years. Although proponents of this new requirement argued that it was necessary for issues of national security, many historians believe that the change was made for political reasons—to limit the number of new citizens who might support and vote for Thomas Jefferson’s Democratic-Republican Party and against the ruling Federalist Party. Indeed, naturalized citizens from Ireland and France did tend to side with the Democratic-Republicans. Considered part of the Alien and Sedition Acts of 1798, this law was repealed in 1802, when Jefferson was president. With the repeal the period of residence necessary to apply for citizenship went back down to five years.

Nineteenth Century Legislation

The Fourteenth Amendment to the US Constitution extended citizenship to all persons born within the territory of the United States, regardless of their parents’ citizenship:

All persons born or naturalized in the United States and subject to the jurisdiction thereof, are citizens of the United States and of the State wherein they reside. No State shall make or enforce any law which shall abridge the privileges or immunities of citizens of the United States . . .

Although the words “All persons born . . . in the United States . . . are citizens” seem unequivocal, there are actually two exceptions to this principle—children of foreign diplomats and children of occupying enemy military personnel.

The Naturalization Act of 1870 made explicit the principle articulated in the Fourteenth Amendment by providing for the naturalization of all African Americans born in the United States, including former enslaved persons.

The 1870 law also established new penalties for fraudulent naturalization applications, and it specified that Asians living in the United States were not eligible for American citizenship. The Chinese Exclusion Act of 1882 further codified these restrictions by forbidding further immigration from China and making even more explicit the ban on naturalization for Chinese residents of the United States. However, a significant challenge to Chinese exclusion came in 1898, when the US Supreme Court ruled in the case of United States v. Wong Kim Ark that citizenship had to be granted to children born in the United States to Chinese parents. Meanwhile, the Geary Act of 1892 continued to enact the ban on naturalization by Chinese residents.

In 1862, Congress had passed a law allowing immigrants who had served honorably in the US Army to apply for naturalization after only one year of residence. In 1894, this privilege was extended to honorably discharged veterans of the US Navy and Marine Corps who had served a minimum of five years. These measures allowed a significant number of Irish immigrants who had served in the Mexican War and the US Civil War to become citizens and helped make possible a strong Irish presence in the politics of such cities as New York, Boston, and Chicago.

The Immigration Act of 1882 sought to exclude “convicts (except those convicted of political offenses), lunatics, idiots and persons likely to become public charges” from entry into the United States. Such persons already in the country were excluded from the naturalization process. The law set up a series of immigration offices at various ports of entry and levied a fifty-cent tax on all immigrants landing at these ports.

Twentieth Century Legislation

The Naturalization Act of 1906 tightened the requirements for naturalization. Prospective citizens had to produce verification of their entry into the United States and verification of the identities of their spouses and children. They also had to demonstrate their ability to speak English. The Emergency Quota Act of 1921 set national quotas for entry into the United States based on 3 percent of the number of residents from each country who had been residing in the United States during the year 1890. The quota system effectively limited immigration from eastern and southern European countries but, perhaps oddly, set no quotas on immigration from Latin America. Consequently, the numbers of immigrants from Mexico and other Latin American countries who applied for naturalization dramatically increased over the next two decades. Meanwhile, the Nationality Act of 1940 sought to clarify the status of those born in United States territories and made residence in the United States a key to retaining citizenship for those born in the United States of foreign parents.

The Chinese Exclusion Act was finally repealed by the Immigration Act of 1943, which was also known as the Magnuson Act. Afterward, a steady stream of Cantonese-speaking immigrants began to enter the United States who were likely to learn to speak English and apply for naturalization. Repeal of the Chinese Exclusion Act also paved the way for Chinese nationals already living in the United States to apply for naturalization. The Immigration and Nationality Act of 1952, also known as the McCarran-Walter Act, added some new restrictions to immigration but granted US citizenship by birth to persons born in the US territories of Guam, the Northern Mariana Islands, Puerto Rico, and the US Virgin Islands. Before this law was passed, persons born in those territories had to apply for naturalization to become US citizens. The Immigration and Nationality Act of 1965 allowed residents of any country of origin presently residing in the United States equal access to the naturalization process.

Special Issues

By the 1980s, illegal immigration had become a concern for many in the United States. The Immigration Reform and Control Act of 1986 addressed the realities of undocumented residents in the United States by providing the opportunity for undocumented immigrants to apply for naturalization provided they could prove that they had been in the United States for at least four years. Although the law was criticized by some for providing “amnesty” to people who had lived in the United States illegally, the legislation included new sanctions against American employers who knowingly hired undocumented workers.

During the 1980s and 1990s, many American couples looked to other countries to adopt children. The Child Citizenship Act of 2000 made the process of naturalization much easier for foreign adoptees. Under this law, children under the age of eighteen who were adopted by American citizens and were under their adoptive parents’ custody automatically became naturalized upon their entry into the United States.

Modern Naturalization Processes

Throughout the twentieth century, the naturalization process evolved. Immigrants who had attained permanent resident status and obtained green cards could apply for naturalization not only after five years of residence in the United States but also afer only three years if they were married to American citizens. Applicants for naturalization had to demonstrate permanent residence in the states or districts in which they made their applications. They also had to show “good moral character,” which was determined through criminal background checks, and “an attachment to the Constitution,” which was demonstrated through a basic civics test. Finally, applicants also had to be able to communicate in basic English and swear an oath of allegiance to the United States.

Between the mid-1990s and the early 2000s, the number of immigrants who became naturalized citizens increased dramatically. In 1996, there were approximately 6.5 million naturalized citizens in the United States. In 2005, that figure had risen to more than 11 million. By that time, almost one-half of all foreign-born immigrants who were legally residing within the United States had been naturalized. Reasons for this large increase in naturalization included several negative incentives, such as the trend to restrict certain public benefits to US citizens. Another incentive to naturalize was a policy that made the cost of replacing green cards comparable to the cost of applying for naturalization.

During the early twenty-first century, the subject of dual citizenship began receiving national attention. At issue was how immigrants can reconcile their dual citizenship with the oath they take in which they renounce their previous citizenship. Despite this apparent contradiction, there have been some high-profile cases of naturalized citizens who have retained their previous citizenship. Former California governor Arnold Schwarzenegger (2003–11), who has retained his Austrian citizenship, is perhaps the best-known example. The US State Department’s policy on dual citizenship has been that the US government does not recommend it but will recognize it. The government recognizes that some newly naturalized citizens may have responsibilities to fulfill to the countries of their birth. For example, naturalized US citizens from Israel may still be liable for Israeli military service that does not affect their US citizenship. However, the Department of Homeland Security has come under criticism for detaining naturalized US citizens traveling with foreign passports.

As the twenty-first century progressed, rates of naturalization continued to be high. In 2022, 24.5 million naturalized citizens resided in the United States, representing about 53 percent of all immigrants. In the 2020s, large numbers of naturalized citizens lived in Houston and Dallas, Texas; Chicago, Illinois; and Newark, New Jersey, among other cities. The fastest-growing segments of the naturalized population came from Mexico, India, the Philippines, the Dominican Republic, and Vietnam. Despite these numbers, policies enacted during President Donald Trump's two terms in office sought to denaturalize US citizens who were suspected of having obtained their citizenship fraudulently. The Trump administration implemented efforts to revoke the citizenship of naturalized individuals and to increase scrutiny of those applying for naturalization, including more rigorous background checks and higher rates of application denials. Such policies created a climate of uncertainty among many immigrant communities, as fears around increased deportation efforts also remained high during this period.

Aligning with Executive Order No. 14161, during President Trump's second term, a new civics test, the 2025 naturalization civics test, was introduced to affect any noncitizens who filed Form N-400, the application for naturalization, on or after October 20, 2025. Any noncitizen who filed Form N-400 before October 20, 2025, was able to take the former 2008 naturalization civics test. The 2025 naturalization civics test includes twenty questions instead of the former ten from a question pool of 128 questions instead of the former 100. Additionally, test takers need to answer at least twelve questions correctly instead of only six, which was the rule before the change. The change was made to raise the standard of knowledge of US history.

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