With the kings having secured the country militarily and politically and with vast agricultural and mineral wealth at their disposal, the nation's population, arts, and religion flourished. In contrast to elitist Old Kingdom attitudes towards the gods, the Middle Kingdom displayed an increase in expressions of personal piety. Middle Kingdom literature featured sophisticated themes and characters written in a confident, eloquent style. The relief and portrait sculpture of the period captured subtle, individual details that reached new heights of technical sophistication.