Jews who live in the West — the Mountain and Pacific states — stand apart from their counterparts in the rest of the country living in the Northeast, Midwest and South. Western Jews — of whom about three quarters live in California and about half of whom live in the Los Angeles area alone — are more likely to be members of the baby-boom generation, living alone or intermarried, raising non-Jewish children, unaffiliated with synagogues or Jewish organizations and identify as Democrats and liberals.

These are just some of the key findings that emerge from a close look at the Jews living in the West Region, as defined by the United States Census, consisting of Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, Wyoming, Alaska, California, Hawaii, Oregon and Washington. The findings derive from a detailed analysis conducted on behalf of the Jewish Journal of the Pew Research Center’s 2013 survey of Jewish Americans.

The findings are particularly illuminating in that — unlike the rest of the U.S. — the vast majority of Jews in the West live in communities where no random-sample Jewish community studies have been conducted for more than a decade. In the two largest communities, Los Angeles last conducted such a study in 1997; in the Bay Area, the last study took place in 2004.

From the Pew data, it appears that about 1.35 million Jews live in the Pacific and Mountain states, about 230,000 of whom are children. The current number of Jews in the region somewhat exceeds the 1.265 million estimated in 1990 by Jack Ukeles, an urbanist and city planner, suggesting only modest growth in the number of Jews in the West, as well as an overall decline in the share of the U.S. Jewish population from 24 percent in 1990 to about 20 percent today.

The Pew data set does not permit finer geographic division of Western U.S. Jewry. However, by extrapolating from the earlier studies, demographers have estimated that about half of Western Jews live in the Los Angeles area, another quarter live in the Bay Area. Much of the remaining live in Colorado, Arizona and Nevada, with smaller numbers in Oregon and Washington. The other Pacific and Mountain states are home to fewer than 10,000 apiece.

In total, the Pew numbers fall short of the population counts maintained by the local Jewish communities in the Western region. The discrepancy means that either Pew researchers undercounted Jews in the West, or that local Jewish organizations, lacking hard data, are drawing over-estimates derived from surveys conducted years ago.

Bursting with boomers

Among Western U.S. Jews in 2013, more were ages 50 to 64 than among Jews elsewhere (35 percent vs. 29 percent), while fewer were ages 65-plus (17 percent vs. 22 percent). The implication: While the aging of the baby boom is reshaping American society and the Jewish community, its impact will be especially felt among Western U.S. Jewry where, in short order, the number of elderly Jews is poised for very rapid growth. The aging of the many Western Jewish boomers will create new demands and new opportunities for a variety of services to Jewish seniors, and will also mean a more rapid dwindling of the conventionally active and contributing members of synagogues, organizations, federations and traditional Jewish communal institutions — groups that have, until now, drawn much of their leadership and donors from middle-aged Jews, many of whom are now poised to age out of the heretofore prime age bracket for communal engagement.

Fewer married, fewer parents, fewer children

Fewer Jews in the West exhibit what might be called traditional family configurations. They are substantially less likely to be married than Jews elsewhere (43 percent vs. 53 percent), a pattern that derives from their far greater tendency to live with an unmarried partner (11 percent vs. 6 percent), and to be divorced or separated (17 percent vs. 9 percent). Consistent with their lower rates of marriage, fewer Western Jews report children at home (22 percent vs. 28 percent), and far fewer adults ages 18 and older report having had three or more children over the course of their lives (11 percent vs. 23 percent).

More intermarriage, less Jewish child-rearing

Far fewer Jews in the West than those elsewhere are married to a Jewish spouse (17 percent vs. 32 percent), in part reflecting their lower rates of marriage and also reflecting their higher rates of intermarriage. Of those married, Western U.S. Jews are far more likely to be intermarried than other American Jews (60 percent vs. 40 percent). For those marrying since 2000, the gap in intermarriage rates is somewhat narrower (65 percent vs. 56 percent).

With the far higher rates of intermarriage among Western Jews, it comes as no surprise that Western U.S. Jews exhibit lower rates of Jewish child-rearing. By the most expansive definition of raising one’s children as Jews, for the oldest child at home, Western U.S. Jews’ rate of Jewish child-rearing trails that of Jews elsewhere (74 percent vs. 82 percent). But when asked whether the child is being raised in the Jewish religion, a more stringent definition, that gap widens remarkably. Just 40 percent of Jews in the West are raising their oldest child in the Jewish religion vs. 63 percent for Jews elsewhere.

Part of the reason for the low rates of raising children in the Jewish religion is attributable to high rates of intermarriage, for sure. But even controlling for marriage (in-married, intermarried and unmarried), for each type of marriage, Western U.S. Jews are more likely than other American Jews to raise children as — according to answer options on the survey — only partially Jewish, or Jewish with no religion.

The fluidity of group boundaries and the growing secularization of Americans in general are trends that are most pronounced in the West. Not surprisingly, in their marriage partners and child-rearing decisions, the Jews of the West are reflecting — and are partially shaping — their region’s individualism and multiculturalism.

Weaker Jewish background

Western U.S. Jews’ intermarriage and child-rearing patterns are also consistent with their own generally weaker Jewish upbringing. They are somewhat less likely to have been raised by two Jewish parents (65 percent vs. 73 percent). Fewer report having been raised Orthodox or Conservative (38 percent vs. 46 percent elsewhere). Far more Pacific and Mountain State Jews report having received no Jewish schooling (27 percent vs. 19 percent); and fewer attended day school for seven years or more (8 percent vs. 14 percent). Not surprisingly, only 15 percent of Jews in the West can understand at least some of the words when they read Hebrew, as compared with 28 percent of Jews in the other parts of the country.

The diminished number with two Jewish parents, denominationally traditional upbringing and Jewish schooling, especially of the more intensive kind, all undoubtedly influenced not only the rates of intermarriage, but also a wide number of indicators of current Jewish engagement.

Few Orthodox, less Conservative, almost half with no denomination

Despite getting “bad press,” denominational identity remains a powerful predictor of so many expressions of Jewish engagement. Hence, the denominational distribution is valuable as a way of comparing Western U.S. Jews with other American Jews. Notably, Western U.S. Jews dramatically trail Jews elsewhere in the proportion calling themselves Orthodox (1.4 percent vs. 11.4 percent elsewhere). The gaps are far smaller for Conservative (15 percent vs. 20 percent) and Reform (36 percent vs. 37 percent). However, quite notably, Jews in the West significantly lead other American Jews in the number who identify with no denomination (48 percent vs. 32 percent).

In sum, the denominational distribution of Western U.S. Jews points to low levels of identification with identities associated with high rates of Jewish involvement, along with a high level of identification with the identity (denomination: none) generally associated with the lowest rates of Jewish involvement. And as we see immediately, the West’s relatively lower rates of Jewish engagement in so many ways are consistent with Western Jews’ denominational distribution, Jewish background, and patterns of marriage and intermarriage.

Weaker Jewish feelings

On several measures of feeling Jewish, Jews in the Western U.S. trail those elsewhere in America. The one exception is being proud to be Jewish, a sentiment that characterizes almost all adult Jews who identify as such (94 percent in the West; 96 percent elsewhere). But substantial gaps emerge between the American West and the rest of American Jewry with respect to several key sentiments, among them: feeling a strong sense of belonging to the Jewish people (71 percent vs. 78 percent); feeling a special sense of responsibility to take care of Jews in need around the world (53 percent vs. 67 percent) and feeling that being Jewish is very important in their lives (38 percent vs. 48 percent). In fact, the more demanding the criterion (where fewer people agree), the greater is the relative gap between Jews in the West and elsewhere in the U.S.

Fewer Jewish rituals

We see the same pattern with respect to a variety of religious practices. Consistently, the Jews of the Western U.S. trail everybody else. This is the case for attending a Passover seder (59 percent vs. 73 percent), attending High Holy Days services (48 percent vs. 62 percent), and fasting on Yom Kippur (43 percent vs. 59 percent). We found similar frequencies for three religious practices — usually lighting Shabbat candles, attending synagogue services at least monthly and keeping a kosher home. For Jews in the Western states, about 15 percent observe each of these. For those elsewhere, we find about 26 percent — not quite double the frequency as in the West. Again, more demanding indicators open proportionally larger gaps between Jews in the West and those in the East, South and Midwest combined.

Less Jewish association, formal and informal

Consistent with the patterns above, on several measures of attachment to other Jews, the West trails as well. Fewer Western U.S. Jews donate to a Jewish charity (42 percent vs. 61 percent); fewer belong to synagogue (24 percent vs. 33 percent); and fewer are members of another type of Jewish organization (20 percent vs. 30 percent). The patterns of thinner ties extend beyond the formal (membership to organizations and the like) and extend to the informal realm (neighbors, friends, family members and spouses).

The Pew survey provides no definitive evidence of residential dispersion, but local population studies tend to show far fewer Jews sharing the same ZIP code in the Western U.S. than in Jewish communities in the East, South and Midwest. As noted above, Western Jews report more non-Jewish parents, spouses and children. In addition, fewer report that most of their friends are Jewish (a stunning gap of 18 percent in the West vs. 37 percent elsewhere) while more in the West report that hardly any of their friends or none are Jewish (33 percent vs. 18 percent).

Explaining the low levels of Jewish engagement

How are we to explain the consistent gaps — from moderate to large in size — in Jewish engagement between Jews in the Western U.S. and Jews in other regions of the United States?

On one level, we have to look at the regional culture. Of all the regions in the country, the West has been the most secular, at least for the U.S.-born (and here, Mexican Americans offer an exception). The American-born in the West match or lead counterparts in other regions with respect to having no religion and low frequency of attending church. Scholars of ethnicity have noted how white European ethnic groups are less identified, cohesive and persistent in the West than are their counterparts elsewhere.

But beyond the regional culture is the undeniable impact of intermarriage and other features of Jewish social networks, or the lack thereof. More Jews in the West than elsewhere were raised by intermarried parents. Correlatively, more married non-Jews, and more have established mostly non-Jewish friendship networks. Surely, the decline of Jewish social networks on the most intimate level both reflects and advances distancing from all forms of Jewish life.

Previous research has focused on the impact of intermarriage on the individual level, showing the emergence of two Jewries: one in-married and in-marrying, the other intermarried and continuing to heavily intermarry. Here, with the Pew data collected on a national scale, we have a chance to examine the impact of intermarriage on an entire segment of the Jewish population. The West versus the rest offers an experiment in real time. The comparison enables us to see the results of sustained high rates of intermarriage in the West versus the result of what may be called only moderate rates of intermarriage (in the East, South and Midwest). Predictably, high rates of intermarriage are generally associated with lower rates of Jewish involvement — however measured.

Jews in the West have long prided themselves on sitting on the forefront of change, anticipating and experiencing the developments that will soon characterize the rest of American Jewry. In the aging of the baby-boom generation, in the dispersal of the Jewish population in residential and social terms, in the mounting levels of intermarriage, and declining levels of Jewish engagement among the non-Orthodox, Western Jewry may well continue to lead the way. And, if so, that would be unfortunate for Jewish continuity, not only in the West but throughout the United States.

Steven M. Cohen is research professor at Hebrew Union College-Jewish Institute of Religion and director of the Berman Jewish Policy Archive at Stanford University. Samuel Abrams is a research fellow at Stanford University’s Hoover Institution and professor of politics and social science at Sarah Lawrence College in New York.