Gresham is a city in the Willamette Valley, Located in Multnomah County in the U.S. state of Oregon, bordered by Portland to the northwest an…Gresham is a city in the Willamette Valley, Located in Multnomah County in the U.S. state of Oregon, bordered by Portland to the northwest and partially in the southwest. it was first settled in the early 1850s by the Powell brothers. It remained unincorporated until 1905; it was named after Walter Quintin Gresham, an American Civil War general and United States Secretary of State.