"All history is the history of thought" is Collingwood's main premise in The Idea of History. Collingwood argues eloquently that to understand past events we must understand the ideas, thoughts and motives behind them. The book begins at the point where Collingwood believes the writing of history began; The Classical era IE. The ancient Greeks. The narrative then moves through the progressing ages and discusses their conceptions of the past and how these relate to ideas of the time.
I read The Idea of History in preparation for writing my personal statement to university. It gave me a great understanding of the inner workings of history. And how our conceptions of the past have changed over time. It is a challenging book. I really enjoyed the parts that i understood. But I had to read certain sections several times to understand exactly what Collingwood was saying.
To sum this book up, albeit in a very simplistic way, i would say it is about the philosophy of history. I would highly recommend it to anyone who questions the way history is written.