The New York Times has an interesting review of the latest book on nineteenth-century European history - Richard Evans' The Pursuit of Power. The review gives a useful oversight of the main themes of the period. There is another very positive review in the Irish Examiner.
Evans' approach is thematic and this might not suit readers who are relatively new two the period. Two more conventional histories are Robert Gildea, Barricades and Borders: Europe 1800-1914, 3rd edn. (Oxford, 2003) and Michael Rapport, Nineteenth-Century Europe (Palgrave, 2005).