One unusual thing about Landsman, however, is that he is a Yiddish-speaking policeman in a Jewish quasi-state. The Yiddish Policemen's Union is set in an alternate world where the United States gave haven in the 1940s to the Jews of Central and Eastern Europe, in the form of the special Federal district of Sitka. Now, sixty years on, Sitka is about to lose its special status, under a Reversion which will see it become an ordinary part of Alaska...
This alternative history is lightly sketched, with exposition limited to a few paragraphs and passing references: to an atomic bomb being dropped on Berlin in 1946, the defeat of Israel in 1948, and so forth. The setting is used more substantially, however, with Yiddish language and Jewish culture used partly as decoration but also to support the characterisation and plotting, which involve Hasidic sects, messianic beliefs, a chess club, and so forth.
The Yiddish Policemen's Union may depend a little too much on its setting: the story is slow moving until it speeds up rapidly towards the end, there's not much of a mystery and no real tension, and one never really comes to worry or care that much about the characters. But there's enough to keep one going — Chabon can write — and the overall result is a decent entertainment and an easy read.