Assuming the Bonanno family as a reference for the Corleones, since Joe such as Vito became bosses in their youth and tried to make his sons the new bosses of their families.

The Godfather begins with the wedding of the daughter of Don with a low level associate, while in reality the daughters of the bosses, especially if Sicilian, marrying on other sons of a mafia boss or a high-ranking mobster such as bill bonanno with Rosalie Profaci;

For no reason it would be allowed to a non-Italian to become a made men, much less a consigliere,the title was gave to old and trusted mafiosi, who had the task of settling the issues. In reality don corleone would adopt tom and would give his surname but wouldn't go further;

The killing of a police captain would have caused a sensation and would create serious damage to the corleones but there would have been no war between families and how strong were the corleone, couldn't fight against all the other families at the same time;

No bosses such as Michael, would have moved his base in las vegas that being open city was of no family in particular, since his power base was in new york;

Corleone family has at least 100 made men including at least 10 capos, while showing only Tessio, Clemenza, Al Neri and others in the new books of the series. Certainly Don Vito knew the two ever since as he was young and had more confidence but doesn't show any other capos;

The idea that a mob boss can't refuse a hearing on the day of the wedding of his daughter is a nonsense; the mob boss have always done what they wanted;

Michael wants to rebel against his family and for this bride Kay and has children who are not full-blooded italians thing that at the time even the bravest of the mob boss sons wouldn't have done (Tommy Gambino married Frances Lucchese);

A non-italian like tom hagen couldn't kill so easily a Chicago Outfit boss without the commission ok;

The bloodlust of Michael: the 5 families bosses killing, the murders of Frank Falcone and Tony Molinari, the Dons of Los Angeles and San Francisco, respectivelyand of Carlo Tramunti of New Orleans. No boss in the american LCN history has the power of whack some many bosses without any consequences.

Furio: First, the Godfather movie and novel are fiction, based on some broad impressions of Mafia that Mario Puzo imagined. But, you are assuming--as do many people on these boards--that the Mafia has hard-and-fast "rules" that are followed by all, so that Mafiosi can appear to be "men of honor" instead of the common criminals that they really are.

The reality is there are very few hard-and-fast "rules." A Mafia Don is like an emperor, and can do almost anything he wants within his family. In that respect, the Godfather may be closer to real life. If a Mafia boss wanted to appoint a non-Italian as his consigliere, who was going to say "no" to him? Are the other families going to declare war on him? Of course not. More than a few Dons did not have formally appointed consiglieri, and just relied on people they trusted for advice. Hugh "Apples" McIntosh, Carmine Persico's bodyguard, was one of his most trusted advisers. A Don would not "make" a non-Italian in a formal ceremony, but so what? They can use anyone they choose to use. Paul Vario, caporegime and one-time street boss of the Lucchese family, used Jimmy Burke, a full-blooded Irishman, as the equivalent of a crew chief because he was a good earner and was trustworthy. No one stopped him.

BTW: Vito Corleone was a composite of several NY Dons. Yes, he was like Bonanno in wanting his son to succeed him as Don. But Bonanno was up to his neck in drugs, and Vito Corleone wanted no part of drugs. Vito was the top olive oil importer to America, as was real-life Don Joseph Profaci. But, unlike Profaci, he never had to contend with a war within his family. Vito Corleone is most like Frank Costello: politically all-powerful, anti-drug, the gambling czar, the "Prime Minister of the Underworld."

Well stated TB.

If a boss is an emperor,why the other made men start the banana war because don't want bill bonanno as boss ?

Make a non-italians as consigliere ? only chicago has in his top enchelor non-italian,the others families donit made non italian as made men or capo or even underboss or consigliere because the others families won't recognize them as equals (when benny egg understand that rocco marinucci wasn't made told him to go away and rebuked Casella, never mind what would happen with a non-Italian).

The rules have always existed after the 1931:

In very family there are a boss,a consiglieri,an underboss and various capos and so the made men; all must be full-blooded italian on recently also half italian.

But the boss can do half-ever what he want example the banana war.

The Godfather was written in 1969, six years after the testimony of Valachi for which Puzo hasn't imagined anything, citing the 5 families, the commission, the relationship between the Sicilian Mafia and their American cousins etc.

As TB posted, The Godfather is fiction. As such, it takes liberties with facts. If it did not, then it would be a narrative documentary.

using Bonanno as case in point, I think all of Vito's sons are base don Bill, Sonny hot tempered, extra martial affair, Bill had both, Michael, college kid kind of out of his element, Bill was in college when he was made, like Fredo some thought he was a little stupid/eccentric (Mary Ferrel Wiretaps)and like Tom he was made to be consigilieri.

The difference between that and real life is that, Vito only had 2 capos, and Bonanno had much more all who did not agree, and some who were tied into other bosses (Gaspar D and Magaddinno) however even Tessio hooks up with Barzini...

A lot of people think Vito himself was based on Frank Costello. One thing I took from reading the Godfather, particularly all of the material involving Johnny Fontane, is that Puzo was no fan of Sinatra.

The feeling was mutual. They almost came to blows in a restaurant.

According to an expert named "Google":

Vito is based on Frank Costello and Carlo Gambino.

Michael is based on Joe Bonanno and Vito Genovese.

Hyman Roth: Meyer Lanskey

Moe Greene: Bugsy Siegel

Johnny Fontaine: Kanye West. duh.