Our ideas about ourselves and the world around us - who we are and how we fit in - arise out of our relationships with our parents in our toddler years. If parents are suffering from the pain of traumas past, that can easily be passed onto the toddlers they nurse and, before they know it, the child will have developed whole ways of thinking and being in the world that has incorporated that pain.
Because of this, our general cultural background has an enormous effect on our psychology. Everything from the way we celebrate success, to the way we mourn our dead to the way we cope with illness is substantially influenced by cultural norms, as well as the way we perceive the world around us and, indeed, the way we perceive ourselves as individuals. The extent to which our cultural heritage plays into our own self image is often underestimated - it's almost like the invisible elephant in our psyche.