518 born in Greece - Washington State County Census Records, 1850-1914
Ancestry.com has recently added an index to the records on the Washington State Archives site that covers County Census Records, 1850-1914. A search shows 518 people who were born in Greece.
Ancestry.com - WEB: Washington, Various County Census Records, 1850-1914 - https://www.ancestry.com/search/collections/70878/
Washington State Archives - https://digitalarchives.wa.gov/