During the First World War (1914–1918), Morley gathered intelligence about and reported on the movements of German operatives in the region, information in which the U.S. Government had a keen interest. According to subsequent investigations, Morley was one of a number of ONI operatives working in the region under the guise of conducting scholarly research. Their mission was to seek out evidence of pro-German and anti-American agitation in the Mexico-Central America region and to look for secret German submarine bases (which proved non-existent). Morley's archaeological work provided a ready excuse to travel the countryside armed with photographic equipment, and he himself traveled more than 2,000 miles (over 3,200 km) along the coastlines of Central America in search of evidence for German bases.