Unlike the story it introduces, the poem was written several years after World War I was over. For the metre, cf. “To W.A.”, by Kipling’s friend W.E. Henley (1849-1903):
Or ever the Knightly years were gone
With the old world to the grave
I was a King in Babylon
And you were a Christian slave.
The title may be intended to recall a passage about changelings in “Cold Iron” (Rewards and Fairies), in which a spell cast on a baby means that “when the babe’s mind came to bud out afterwards, it would act differently from other people in its station.” Cf. also the ex-soldiers in the earlier poems “Shillin’ a Day” and “Chant-Pagan”, both of whom find that civil life means loss of status.