My grandparents emigrated to the US from Eastern Europe. They had a very interesting mix of wanting to hold on to tradition while at the same time adapting. On the one hand, they were all members of a church that held services in Hungarian, lived in the Hungarian section of Cleveland and maintained traditions like the having a celebration at harvest time. On the other, they all taught themselves to speak, read and write English, and insisted their children speak English. (Interestingly, my mother found out as an adult that the only Hungarian she knew was what amounted to baby talk!) So, I don't think it was at all unusual for Peter's father to want to assimilate and be a successful part of the culture around him, and impacted how he raised his children.