Clarence Dayton "C.D."Hillman., self-described as "promoter" and "capitalist" was one of Seattle's wealthiest men in 1903, but due to his notorious dealings in real estate development, eventually spent time in the federal penitentiary at McNeil Island on 13 counts of U.S mail fraud.

C.D. Hillman was known to sell nonexistent real estate to newcomers including properties located at the bottom of Green Lake and land in a town he called Birmingham, north of Everett, which consisted of a fake general store and sawmill to impress prospective buyers. He was also known to sell the same property to different people and to readjust property lines after the sale.

The Hillman Investment Company platted and sold properties in Hillman City, Kennydale, and Rainier Beach, having sold over 7,000 lots in Seattle by 1902 as well as properties in Southern California after C.D. Hillman served his 18 month prison sentence.

C. D. Hillman passed away in 1935 and his gravesite is in the Lake View Cemetery, in Seattle, Washington.