Donald Macleay was a 19th century merchant and banker in Portland in the U.S. state of Oregon. A native of Scotland, he emigrated at the age of 16 with his parents to the Canadian province of Quebec before relocating as an adult to California and, later, Oregon. With his business partner William Corbitt, he established a highly profitable wholesale and shipping business in Portland that centered on groceries and liquor, then wheat, salmon, and timber exports. He invested in Oregon railroads, served for a time as president of the Portland Board of Trade, and is generally credited with founding the U.S. National Bank of Portland, of which he was president toward the end of his life.

The Arlington Club is a private social club organized in 1867 by 35 business and banking leaders of Portland in the US state of Oregon. First called the Social Club and later renamed the Arlington Club, it offered its all-male, largely white membership consisting of banking and business leadership.