Guest Dave, I would challenge this,
. People believed what they were told not because they were religious but because they were stuck in a mindset of subservience to the upper classes.

Firstly, the "upper classes" too went willingly to war and suffered such disproportionate losses that it finished them.

Secondly, there was no sign of that subservience just before the war.
Britain was riven with strikes and industrial disputes, and there were mass demonstrations against involvement in a European war.
All that stopped when Belgium was invaded.

The people were told that by their independent press, and by the streams of refugees.
They believed what they were told because they knew it to be the truth.
Modern historians say they were right.