Mario Puzo: The Godfather

I guess more people would have seen the Godfather movies rather than read the book; but let me start by saying that this is a great book. The book is a fairly gripping book, establishing both the history of why the godfather became the godfather (Vito Corleone), and also the birth of the next Godfather, Michael Corleone. It does meander a bit in between when trying to explain various things, but overall is a very taut book.
The book takes the Corleone family, one of the 5 mafia crime families and the tensions between them. The book explains the motives and the development of characters for some of the main characters of the book, Vito Corleone, Sonny Corleone, Michael Corleone, Connie, Kay (Michael's wife), Tom Hagen, and a few others, but whose characters are not so well developed.
The book also explains numerous mafia activities to people who may not be well-enough acquainted with some of these terms, terms such as button man, hitting the matresses, omerta, La cosa nostra, etc.
The story explains how a poor Italian immigrant, a man of quiet nature, but internally a very powerful individual, slowly starts to be seen as a man of power, a man of stature and one who can influence things. He can get his people justice, deferment from the army, rough justice against anyone who has harmed them and so on. While reading this book, it would not seem strange at all that all these activities are illegal :-), they just seem natural. Slowly, he starts to build an empire consisting of political connections, book-keeping, races, and many other vices including the illegal running of alcohol. However, even such people have their own scruples, such as being against prostitution and drugs.
And this is what brings him down and decides the rest of the book. Vito refuses help to another family seeking to expand in the drugs field, and provokes an assassination attempt in which he is injured, and which brings his violent son Sonny into the field as the interim leader (his other son Michael is outside the family business, being a decorated soldier). Hence, in a quirk of fate, Michael gets involved, kills 2 people and escapes the country. In the ensuing gang warfare, Sonny is killed and Vito Corleone, The Godfather, gets up from his sick bed in an attempt to ensure the safe return of his son Michael back.
Vito makes a deal in which he accepts Sonny's death and foreswears all vengeance (although he is perceived as weak due to this lack of revenge) in order to get Michael back. The aim of course is long-term, to get Michael to take the revenge after setting him up as the Godfather. The latter part of the book is about this effort; how Michael gains the power of the family, how he turns from being a loyal American to the head of a major criminal family, and how he eventually carries out the revenge (by killing a number of the opposition families leaders, and also killing his own brother-in-law for the role he had in getting Sonny killed).
It is only at the end where the author puts a touch about that these people are bad people, when you see that the women of the family are praying for their souls. The book also depicts women and the African-American community in a bad light, thus depicting the inherent racism of the Italian (and maybe others) community as of that time.