Population: Approximately 766,135 residents (the most populous of Oregon's 36 counties). Geography: 465 square miles (the smallest of Oregon's counties). Cities: Fairview, Gresham, Maywood Park, Portland, Troutdale, Wood Village. County Employees: About 5,600 people. Functions: Services for seniors and disabled people, animal services, assessment and taxation, bridges, community justice, courts, elections, health, jails, libraries, marriage licenses and passports, school and community partnerships. Elected officials: Four commissioners elected to the board by district. Elected countywide are a board chair, sheriff, district attorney and auditor. County History: Created on Dec. 22, 1854 and named after native people in the region.