The Rough Guide History of India
The book tells of the early epics such as the Ramayana and the Mahabharata, and describes religious developments including the adoption of Buddhism and the origins of Hinduism. The rise of Islam greatly affected India with the formation of Sultanates within the subcontinent, as well as the founding of the Mughal empire. Getting closer to the present, we hear of the arrival of the East India company, and the gradual spread of British rule to the whole of India. Then came Gandhi, and the last chapter deals with India and Indian politics since independence in 1947.
This is meant as a reference book, so that the reader can find information relevant to a given period of time, but it is actually surprisingly readable, especially in the later parts (earlier on it's sometimes hard to keep track of the shifting boundaries within the subcontinent). The author manages to pack a great deal of information into a very small book, and I'd recommend it to anyone who wants to have such a wide overview quickly to hand.