Why did Superman change the yellow in his “S” shield to black for a while?
At the end of the war with Imperiex (“Our Worlds At War” 2001), in which many thousands of people lost their lives, including Lois Lane’s father, Wonder Woman’s mother and (for a time) Aquaman, Superman decided to change the yellow in his “S” shield to black as a mark of respect to those who died. Around a year later he changed the colors back to the familiar yellow.