This is a fascinating book, not a mere footnote to history but a revealing visit backstage behind the offical facade. Born in and from violence, the Irish State was from the start highly security-conscious, particularly towards the threat posed by the IRA. Neutrality in the second World War brought extra problems and a much wider political context, with wartime Britain pressing the Irish authorities to clamp down on the activities of the German Ambassador, Hempel (whose radio transmitter was eventually impounded and stored in a bank vault). Goertz, the rather enigmatic and ineffective German agent, is traced in his curious career and there is much light shed on the entry of Continental emigres, including Jews. De Valera, it seems, wanted a "liberal policy" towards admitting them, but officialdom raised obstacles, notably the Department of Justice, so in the end only a miserable minority was allowed into Ireland. The complex postwar and contemporary situations are also well dealt with.