the most progressive of all ideas, the idea that the human
race could and should breed a superior version of itself.
In the Nazi experience, history demonstrated the wisdom of his
once "reactionary" views. 

His poetry runs the gamut from the comic 1908 "On Running After
One's Hat" to dark and serious ballads.  During the dark days of 1940,
when Britain stood virtually alone against the armed might of
Nazi Germany, these lines from his 1911 Ballad of the White Horse
were often quoted: 

I tell you naught for your comfort,
Yea, naught for your desire,
Save that the sky grows darker yet
And the sea rises higher. 

Though not written for a scholarly audience, his biographies of
authors and historical figures like Charles Dickens and St.  Francis
of Assisi often contain brilliant insights into their subjects.
His Father Brown mystery stories, written between 1911 and 1936,