National identity is normally based on a people's shared history. If that history is very old, much of it may be apocryphal or entirely mythical. A prime example is the history of the Jewish people who trace their national identity to the flight of the Hebrews from Egypt. This is exemplified by the Passover celebration which they still maintain. These same people still identify themselves as God's chosen people, based on the apocryphal words of God to Abraham who ordered Abraham to seal the covenant with circumcision, still an important rite in Jewish faith.
Johan Herder saw national identity as being a natural development from shared history:
Nature brings forth families; the most natural state therefore is also one people, with a national character of its own. For thousands of years this character preserves itself within the people and, if the native princes concern themselves with it, it can be cultivated in the most natural way: for a people is as much a plant of nature as is a family, except that it has more branches.
Gender roles are more problematic; although it appears that those societies whose creation myths speak of a 'great mother" tend to be matrilineal in nature. This was true of African societies and early American Indian societies. The Eastern Woodland Indians in fact were matriarchal, with the tribal council composed of the women of the tribe. This was seen as a natural extension of their role as keeper of house and home.
In short, the acceptance of apocryphal traditions is often the defining characteristic of a nation of people.