After two out of three European Jews were slain in the Holocaust, only a small number of Jews remains in Europe. How is it, then, that there is a widespread and growing infatuation with Jewish culture there? Gruber (Upon the Doorposts of Thy House; Jewish Heritage Travel), who has traveled extensively throughout Europe, attempts to explain this phenomenon. (She should not be confused with the prolific Ruth Gruber, whose account of 1,000 Jewish refugees placed in a military camp in Oswego, N.Y., in 1943 became the subject of a CBS miniseries in 2000.) Gruber finds persuasive evidence of interest in what she calls "Things Jewish," grouping them into three categories: Jewish archeology, which refers to cemeteries, synagogues and ghettos, either restored or rebuilt; "Museum Judaism," which includes Jewish heritage travel as well as Jewish museums; and Yiddish music, also known as Klezmer. Through direct observation, Gruber seeks to describe and understand how these expressions of Jewish culture have become popular even though there are so few Jews left in Europe. While she does not provide a definitive answer, she suggests, among other reasons, that the embrace of Jewish culture by non-Jews in Europe may signify atonement for the Holocaust, adherence to a multicultural ideal or a way to redefine "personal identity and national histories." Whatever the explanation, Gruber asserts that a "virtual Jewish world" has been created by "virtual Jews." This thoughtful narrative is rich in documentation and provocative in the issues it poses. (Jan.)