* The natural world: Pacific Grove's beautiful coastline, the Monterey Bay, and its diverse marine life were a constant presence. Steinbeck's love for nature and its impact on humanity is evident in his works like "Cannery Row" and "The Pearl."
* The fishing industry: Pacific Grove was a major center for the sardine industry, which Steinbeck witnessed firsthand. The lives of fishermen and the changing economy of the fishing industry are vividly depicted in "Cannery Row," "Tortilla Flat," and "Of Mice and Men."
* The community: Pacific Grove was a small, close-knit town with a unique blend of residents, including artists, writers, and laborers. The social dynamics, class struggles, and human interactions within this community likely informed Steinbeck's portrayals of characters and relationships in his novels.
* The social issues: Steinbeck was a keen observer of the social issues of his time, including poverty, inequality, and the impact of industrialization on society. These issues were prevalent in Pacific Grove and are explored in many of his writings.
* The sense of place: The specific setting of Pacific Grove, with its unique geography, history, and character, provided a distinct backdrop for Steinbeck's stories. This sense of place permeates his works, giving them a sense of authenticity and depth.
Therefore, it's not possible to isolate one element as the most influential. It was the combination of the natural world, the fishing industry, the community, the social issues, and the sense of place that profoundly shaped Steinbeck's literary vision and contributed to his enduring legacy.