A great heaving book involving hundreds of characters and scenes. As other reviewers, it did take me months to finish it, but it was never boring or tedious. Most of the book involves the invasio by Germany but as happened in history the Soviet Union invaded three weeks after the Nazis pursuant to their Non-Aggression Pact's secret codicil dividing up eastern Europe between them. The prideful hopes that Poland took in their infrequent defeats or holding up of the Germans was then shot to hell when the largest nation on earth also invaded them. Does this have the famous charges by horse cavalry against machine guns and gun batteries? Yes, and one feels one lives and dies with those Polish lancers as they gallop toward barbed wire, machine gun nests and stationary tanks.
If you have read Dr. Zhivago, there is much similarity due to the vast number of characters and events (even though Zhivago is about the Russian Revolution and its consquences rather than an external war). The Thousand Hour Day is also full of sublimated (deserved) anger at the British and French allies for their failure to attack Germany during the month it invaded Poland - and at the cynical American correspondent for his detachment. The one armed general at the heart of the book seemed SO much like a character destined to be played by Yul Brynner, that I had him in mind throughout.
The bloodshed, the gore is horrific - and yet probably necessary to drive home the emotional power of what the Poles sought to accomplish - to survive as a nation. Ths is the first of a trilogy - the next books are The March and Valedictory. I won't be able to resist them! :) But in the meantime, I'm reading far lighter material - Pride and Prejudice anyone? :))