Final answer:
Erich von Däniken was inspired by Graham Hancock, H. P. Lovecraft, Kenneth Feder, and Ignatius Donnelly, who influenced his theories on ancient aliens and their impact on human civilization.
Step-by-step explanation:
Erich von Däniken, a Swiss author, was inspired by a variety of sources for his theories, including Graham Hancock, H. P. Lovecraft, Kenneth Feder, and Ignatius Donnelly. These individuals and their works influenced his ideas about ancient aliens and their influence on human civilization.
For example, Graham Hancock's book Fingerprints of the Gods explores the possibility of advanced ancient civilizations, which aligns with von Däniken's theories. H. P. Lovecraft's fictional writings about ancient alien beings also influenced von Däniken's ideas.