1.2 Literature Review
1.2 1 For the research of “The Godfather”
At present, the scholars have a certain research in characters of “The Godfather”. In abroad study, “A History of American Popular Fiction” combing the American popular literature, especially opened a specialized content to describe “The Godfather” trilogy, and pointed that it has an important position in the Italian-American immigrant literature. Gardaphe, Fred(1996) analyzed Italian-American literature respectively by perspective of history, philosophy, and culture. Professor Norton and Kaplan(1997) from Harvard University proposed “balanced scorecard” which provided a starting point for us to understand the strategic development of the godfather's family.

In the paper “Explore inpidual psychological characteristics of godfather in <Godfather> ” , Liang Yanjun said that “Starting from the process of socialization of the Corleone family, and treat upbringing of family as the main line, the author gives us a detailed account of how the two generation godfather transformed from an ordinary person to a boss under the family, the education and the social environment influence. Among  three godfathers,  the history of entrepreneurship created by Vito Corleone showed his strong personality and ability to have great magic powers to protect the family, and his spirit of pursuing money, power and status. And then Mike Corleone had become a new generation of Mafia godfather from a mere college students. In this process, it showed the second godfather Mike's struggle motivation for revenge , and his beliefs and aspiring were stronger than his parents. The author shaped a clever, capable unfeeling character”(Liang, 2007: 99).
Huang Weifen in “<Godfather> trilogy Family" analysises at different levels for “The Godfather” in describing the role of the family, she pointed out that an important factor which lead “ The Godfather ” to be a great success is in gangster type novel. “the author put into the families elements in which the family is not only the story of the narrative space, but also played as a narrative motivation functions to grudge family and retaliation in the gang, at the same time as a result of gang revenge, the emotion between family members hurt ”(Huang, 2008: 127).
In “ Analysis <Godfather> based Human Theory Perspective ”, Gao Jianmei analysis the character of Godfather from anthropological point, “Whether it is old godfather or a new godfather, he struggled for his family. And in the process, their struggle reflects the ‘human’ shadow. Although they were gang leaders, they were not ruthless, cruel, overbearing,also they have their own gentle and sadness. It is their human sides that led The Godfather to a firm position in American Gangster fiction ”(Gao, 2014: 38).

1.2.2 Research related to role conflict theory

Role conflict theory has been one of the key sociological and psychological research, it is an important part in social role theory. Everyone living in the society who have their own role, this role gives him responsibility to bear, and the rights to enjoy, but the role of the requirement is not always consistent with the requirements of the inpidual(Zhang, 2009). When the role conflicts demands and requirements of the inpidual , it creates a phenomenon of role conflict, and this may have an adverse impact on the outside world and themselves.
For now, scholars did not have a precise definition of role conflict. Lin Chongde(2003) think that the role of conflict refers to an inpidual to play a unified role in life by the different requirements of his role and cause conflicts within the role. Cui Daoyi(1987) believes that the role of conflict refers to the ability of inpiduals unable to meet the expectations of all kinds of roles, resulting in personal situations of internal pressures or problems. Woodward(1989) believes that the role of conflict means that it is difficult to select an inpidual for their role behavior, including the heart that creates a confusion, tension, hostility, and the feeling of uncertainty. 从角色冲突理论角度探究《教父》系列三代教父的性格转变及对家庭事业的权衡(2):http://www.youerw.com/yingyu/lunwen_23853.html