John Steinbeck allowing Steinbeck to spend a full day on the set of "The Grapes of Wrath" and the next day on the set of "Of Mice and Men." In the 1930s and 1940s, Ed Ricketts strongly influenced Steinbeck's writing. Steinbeck frequently took small trips with Ricketts along the California coast to give himself time off from his writing and to collect biological specimens, which Ricketts sold for a living. Their joint book about a collecting expedition to the Gulf of California in 1940, which was part travelogue and part natural history, published just as the U.S. entered World War II, never
John Steinbeck appeared in the December 1945 issue of Woman's Home Companion magazine as "The Pearl of the World." It was illustrated by John Alan Maxwell. The novel is an imaginative telling of a story which Steinbeck had heard in La Paz in 1940, as related in "The Log From the Sea of Cortez", which he described in Chapter 11 as being "so much like a parable that it almost can't be". Steinbeck traveled to Mexico for the filming with Wagner who helped with the script; on this trip he would be inspired by the story of Emiliano Zapata, and subsequently wrote