Reading Hans Joachim Moser's 1958 book Musikgeschichte in 100 Lebensbildern (Music history in 100 Biographical Sketches). Moser (g) was a famous German musicologist and prolific author of books about Western music for a high-middlebrow audience. Moser's biographical sketches are lively, readable, but also sophisticated -- he gently dismantles myths such as Palestrina 'saving' Catholic religious music, and isn't afraid to point out works and composers he thinks are under- or over-rated. Moser was also a Nazi, joining the party in 1936 and becoming a senior musical functionary. Among other dubious deeds, he oversaw the 'Aryanization' of Händel's oratorios in the early 1940s.
The book isn't ideologically inflected, though. Granted, lesser-known German composers (Schein, Schütz, Scheidt, Biber even Oswald von Wolkenstein) get more attention than they might in a book by a Frenchman, but this is to be expected. Moser is by no means parochial, and if you ask me, many of these German masters are a bit underappreciated outside of Germany.
At once point, Moser refers to the Lebenswallen of the well-traveled Orlandus de Lassus, which caused me to sit up and say: 'What the fuck ist ein Lebenswallen'? Leben is life, and forms the root of many German compounds: Lebenslust, Lebensauffassung (idea of what life is for), lebenslang (lifelong), even the useful Lebensmüde (tired of life, used of someone who's either suicidal or about to do something extremely stupid and dangerous, as in 'You're really going to drink that piss-colored Sochi tapwater? What are you, Lebensmüde?).
Wallen is a verb meaning, variously, to seethe, bubble or flow. So apparently a Lebenswallen is a seething, bubbling, foaming flow of life. I could find only very few uses of the word in German. One of these is typical, from an 1821 book entitled 'Investigation of Life-Magnetism (Lebensmagnetismus) and Clairvoyancy' by one Johann Karl Passavant:
The middle paragraph reads: 'From the unsearchable depths of Being, universal Father of things, emerges the God-revealing life-source of all existence, the eternal word of creation (the Logos), and the worlds are created and disappear through the flow of life (Lebenswallen), the breath (spirit) of God, who, all-inspiring, fills the universe.'
Lebenswallen, like Afterkind, seems to have fallen into disuse. Together, we can and will usher this fine word back into everyday use.