Virginia leads the nation in the percentage of marriages between blacks and whites, a new study by the Pew Research Center shows, barely four decades after state laws criminalizing interracial marriage were struck down by the Supreme Court. And one in five new married couples in the District crossed racial and ethnic lines.

The prevalence of intermarriage in and around the Washington area reflects demographic changes that are pushing interracial marriage rates to an all-time high in the United States while toppling historical taboos among younger people.

According to the Pew study, about 15 percent of new marriages in 2010 crossed racial or ethnic lines, double the rate from three decades ago. Intermarriages comprise 8 percent of all marriages now, up from just 3 percent in 1980. And most Americans tell pollsters they are untroubled at the prospect of intermarriage in their own family.

“In the past half century, intermarriage has evolved from being illegal, to being taboo, to being merely unusual,” said Paul Taylor, director of the Pew Research Center. “With each passing year, it becomes less unusual. . . . The face of the country is changing, and behaviors are changing with it.”

The study, called “the Rise of Intermarriage,” found patterns that varied by gender, geography and race or ethnicity.

For example, black men were almost three times as likely to marry someone of another race as black women were. Conversely, Asian women were twice as likely to marry outside their race as Asian men were. There was no difference between genders for Hispanics and whites.

In the District, intermarriages account for 19 percent of all newlywed couples, compared to 14 percent in Virginia and 12 percent in Maryland. The only states where intermarriage is more common lie west of the Mississippi River.

But the biggest differences are between different races and ethnicities. The share of whites who marry “out” of their race has more than doubled since 1980, to 9 percent. The percentage of blacks who marry non-blacks has more than tripled, to 17 percent. Asians and Hispanics have the highest rates of intermarriage, with more than a quarter of all Asian newlyweds marrying a non-Asian. But that rate of Hispanics who marry non-Hispanics hasn’t changed since 1980, while the percentage of Asians who intermarry has dipped a bit.

Sociologists and demographers attribute that to four decades of immigration that has increased the pool of Hispanics and Asians who are potential mates.

“Because of the increase of the marriage eligibility pool of Asian Americans, the option of marrying outside in order to have a higher or middle-class lifestyle is much less,” said Larry Shinagawa, director of Asian American studies at the University of Maryland. “You have a higher probability of finding someone of the same ethnic or cultural background.”

Christian Oh, who teaches Asian culture at the State Department, never imagined while growing up that he would marry another Asian.

He came to the United States from South Korea when he was 2, in the early 1970s, so his father could work for his PhD at Iowa State University. It seemed to him at the time that “there were no other Asians in a 400-mile radius” of Ames.

Eventually, the family ended up in Roanoke, where he was practically the only Asian in his high school. He dated girls who were white, black and Hispanic, and ended up going to his prom with an exchange student from India.

Only when he attended college at George Mason University did he start dating other Asians. He met his wife, Sarah, when she returned a pair of jeans at a Gap store where he was working. A new immigrant, she only spoke Korean.

Oh said he found an “ease” in dating a woman with a shared cultural background. The couple wed in 1997 and live in Merrifield.

“There are always going to be cultural explanations with someone who doesn’t understand Asian culture,” said Oh, who has one brother with a wife from Taiwan and another brother who married a white woman.

Non-Hispanic whites make up nearly two thirds of the population, so because of sheer numbers, the bulk of intermarriages have a white spouse.

As intermarriage rates have grown, attitudes have changed dramatically. In a 1986 Roper Poll, two-thirds of the people said they could never imagine themselves marrying someone from a different race. In a 2009 Pew poll, just 6 percent of whites and 3 percent of blacks said they would not accept an interracial marriage in their family.

Dan Lichter, a Cornell University sociologist who has studied intermarriage, said the trend shows the continuing blurring of racial boundaries.

“Different racial and ethnic minorities are increasingly sharing the same social space, in their neighborhoods, their job settings and schools,” Lichter said. “It’s a reflection of declining inequality on a lot of fronts, including income and education.”

But a postracial society remains a long way off, he added.

“Most of the minorities who outmarry are not marrying other minorities,” Lichter said. “They’re outmarrying to whites. It’s not a melting pot.”

Nathan Nash, a black man who is divorced from a Korean American woman he was married to for five years, said that is particularly true for African Americans. A technology consultant who used to live in the District and now lives in Orange County, Calif., Nash said he has Asian friends who would not consider dating blacks.

“In the U.S., race pretty much comes first,” he said. “People are slightly more open to the idea of interracial marriages. But as a country overall, we really identify people first as their race or ethnicity. There’s still a barrier there.”

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