 His older friend and mentor Ernst Thrasolt introduced Ehlen to the ideas of the catholic youth movement that formed shortly before WW I, parallel to the already existing groups of the Wandervogel.Ehlen distinguished himself with lasting effect in this young movement.His maxims were based on the Lebensreform (German reform movement which criticised the industrialisation and wanted to go "back to nature") and the sermon on the mount as well as on closeness to nature and an attachment to his home-country.