James Fenimore Cooper 1789-1851 was a prolific and popular writer whose historical romances of frontier and Indian life in the early American days created a unique form of American literature. He lived most of his life in Cooperstown, New York, established by his father. A life long Episcopalian, he attended Yale but dropped out after three years, discontented with college life. He then served in the US Navy as a Midshipman, something that informs many of his writings. He is best remembered as a novelist, his most famous work being The Last of the Mohicans which I confess I have never read.
Bonhoeffer uses a similar phrase 'worldly Christianity'. It's J Gresham Machen that I want to line up most closely with. See his Christianity and culture here. Having done commentaries on Proverbs (Heavenly Wisdom) and Song of Songs (Heavenly Love), a matching title for Ecclesiastes would be Heavenly Worldliness. For my stance on worldliness, see 3 posts here.