One factor that would make it possible is the decrease in the number of deaths, which could be a result of improved health care. In a country which a very low life expectancy in 1970 (50 years) an increase can be achieved easily with small health improvements and in fact it increased to 65 years since 1970s.
Nazi leader Adolf Hitler violates the Treaty of Versailles and the Locarno Pact by sending German military forces into the Rhineland, a demilitarized zone along the Rhine River in western Germany.