Interestingly this poem (published in Kipling’s collection: A Diversity of Creatures 1917) is originally entitled “The Beginnings” and refers to the “English,” not the “Saxon.”
It is a poem twinned with the short story “Mary Postgate,” which deals with anger at the destruction of innocent lives by the Great War.
Given that it is (with Kipling at this time) emphatically anti-German in sentiment, it’s somewhat ironic that the poem is now known by a title (and with the subject altered in its climactic lines) that might be taken to include Germans.