William Walker McLellan (1873–April 11, 1960) was born in Glasgow, Scotland.
He came to the United States at the end of the nineteenth century and began working at a department store in Newark, New Jersey.
He became a manager of the first S. H. Kress store in Memphis, Tennessee, and then joined McCrory Stores as a vice president.
He lost control of the company during the Great Depression to United Stores Corporation and left soon thereafter.
He then founded the W. W. Mac Company, a chain that he built to 70 stores at the time of his death.