Complex sentence: After the reactivation of her husband in World War I and his rise to the highest military functions, she took over mainly charitable works, such as personally caring for the war wounded and founding the Gertrud von Hindenburg Foundation for moral strengthening of German youth.
Split into simpler sentences: After the reactivation of her husband in World War I and his rise to the highest military functions took over mainly charitable works. So they took care of the war wounded and founded the wife Gertrud von Hindenburg Foundation for moral strengthening of the German youth.