Born in New York in 1929, raised in Germany. After graduating from the Academy of Fine Arts in Stuttgart, he returned to America and worked as a graphic designer. In 1968, he published his picture book "1, 2, 3, Animal Enthusiast" (Bologna International Children's Book Exhibition Graphic Grand Prize), and since then he has become a well-known picture book author all over the world. His representative works include "The Very Hungry Caterpillar", "Brown Bear, Brown Bear, What Do You See?", "Papa,Please Get The Moon!". He died in May 2021.