While Paul Klee's first career breakthrough occurred during his trip to Tunisia in 1914, he experienced another moment of unexpected artistic inspiration during the First World War, when, at the end of 1918, he spent a quiet afternoon in his office at the Royal Bavarian Flying School V in Gersthofen near Augsburg. "Everything is sinking around me," he described to his wife Lily, describing this state of heightened creativity, "and good works arise before me of their own accord. Graphically, in particular, ripe, astonishing fruits are now falling." The existential tensions of the war, combined with inner withdrawal and continuous artistic work, had evidently led to a special state of mind in which Klee himself was overwhelmed by his creative power and finally found his own visual language. From then on, seemingly childlike awkwardness stood alongside painterly refinement, cubic tectonics alongside flowing colors, and nocturnal romanticism alongside abstracting symbolism. Klee's output from 1917 to 1919 was prolific and led to his breakthrough with an art-loving public who, captivated by the poetry of his "magic formulas" and "hieroglyphs," elevated him to a cult figure in the contemporary art scene. Franz Marc and August Macke—best friends—had already fallen in 1917. One can surmise that dark cityscapes, such as those in "Stars Above the City," were not merely fairytale nocturnes for him, but also stemmed from the real experience of wartime blackouts. Franz Marc, August Macke—who had been best friends—had already fallen in 1917. ...