Lewis L. McArthur believed names allow people to think about their own localities and to understand their history. He acted on that belief through decades of work documenting Oregon placenames by serving on the Oregon Geographic Names Board from 1958 to 2006 and compiling and publishing four editions of Oregon Geographic Names.

McArthur was born in Portland on May 22, 1917, about two weeks after his father—Lewis Ankeny “Tam” McArthur—began compiling research on Oregon placenames. Tam McArthur had been inspired by a series of Oregonian editorials by Harvey Scott calling for such documentation. He created the original compilation from information gained from his voracious reading of Oregon history, correspondence with postmasters, and communication with local people during trips and through letters. Tam McArthur published the first edition of Oregon Geographic Names in 1928 and a second in 1944. After his wife, Polly Hewett McArthur, died, he married Nellie Pipes, longtime librarian at the Oregon Historical Society. Tam McArthur completed most of the manuscript before his death in 1951, and Pipes prepared the third edition of Oregon Geographic Names for publication in 1952.

McArthur’s family history runs deep into the exploration and EuroAmerican resettlement of Oregon. His paternal great-grandfathers were Navy Lieutenant William Pope McArthur, who led the 1850 Pacific Coast Survey, and James W. Nesmith, sergeant-at-arms for the 1843 overland migration to Oregon and later a US senator and representative. His grandmother, Harriet Nesmith McArthur, was a founder of the Oregon Historical Society and served on its board of directors from 1898 to 1924. His mother’s father was Henry Hewitt, who came to Portland from England in 1868 and was active in the marine insurance business.

McArthur graduated from Lincoln High School and earned an undergraduate degree in economics from the University of California, Berkeley in 1938. He worked for the Columbia Steel Company in northwest Portland and was called to active duty in the US Army in 1941, serving in the Aleutian Islands until being discharged as a major in 1945. He married Joyce Abigail Clark of Eugene on January 19, 1946, and had a forty-year career with the Ray F. Becker Company in the metal-building business.

Lew McArthur compiled the fourth edition of Oregon Geographic Names, which was published in 1974, the fifth in 1982, the sixth in 1990, and the seventh in 2003. All were published by the Oregon Historical Society Press. The book documents the histories of over six thousand placenames and is a national model for such compilations. McArthur's research methods were similar to those of his father, and he also relied on correspondence from local people to add to the record.

For his generous and significant contributions to Oregon’s understanding of the past, McArthur received many awards and appointments. An avid hiker and climber, he was a longtime member of the American Alpine Club and the Alpine Club of Canada. He was a member of the American Name Society, serving as its president for two years, and the Canadian Society for the Study of Names. The American Association of State and Local History recognized him in 2005 with a merit award for individual achievement. In 2006, the Oregon Geographic Names Board honored his long service by placing his name on McArthur Mound in Wasco County.

McArthur died at the age of one hundred and one on August 29, 2018.