Everything from 1900 to 1955 is already told.
There's roughly a ten year gap in between the war of the '30s (covered in the novel) and Connie's wedding. That's really the only time period not covered.
I'm not sure what you mean with "gap" because there's as much information in the novel about the period after the war with Maranzano (Vito tries to united different groups, buys the compound, etc.) as there is written about the 1920s.
Ofcourse, as the whole period of 1901 to 1945 is only one chapter, it can be a lot more specific.
But what I really would love to see (and I'm sure I'm not the only one around here) is what happened between 1959/1960 and 1979.
The 1960s was a very interesting period for the American Mafia. We can now only speculate what happened with the Corleone family in those years and its transition to legitimacy.
I'm interested to know how Joey Zasa made his bones and eventually became boss of the Corleone's criminal faction. Or who Don Altobello exactly was. When Michael finally made the decision to go legitimate. You name it.
