Mr McMillon, 47, is younger than Mike Duke, who he succeeds, but unlike Mr Duke, 63, he joined Walmart when Walton, who died in 1992, was still the company’s chairman.
Stories about the frugal folksy founder are key tools for Walmart executives and Mr McMillon’s include how on his first day as a buyer at head office he found a Post-it note from the boss complaining that the fishing line at Walmart was not as cheap as at Kmart.
It is no coincidence that as Mr McMillon rose through the ranks he became known as a favourite of Walton’s now grey-haired children, who are still Walmart’s controlling shareholders with a combined stake of about 50 per cent.
Mr McMillon, who is from Walmart’s home state of Arkansas, first worked for the company in 1984 as a teenage summer worker at a distribution centre.
Six years later, in 1990, while studying for his MBA at the University of Tulsa, he rejoined Walmart at a store in Oklahoma, before moving to the head office in Bentonville, Arkansas, the following year.
As he got promoted his easy-going charm marked him out. Mr Duke’s demeanour in public can be rather wooden and when the two men appeared together in recent years Mr McMillon tended to outshine him.
The new chief executive spent most of his career in Walmart’s US division, with stints in food, clothing and general merchandise. From 2006-09 he led Sam’s Club, a warehouse store named after the founder that sells merchandise in bulk.
In February 2009, Mr McMillon took over as president and chief executive of Walmart International, which has more than 6,300 stores and 823,000 staff in countries outside the US.
The international business had been an exemplary engine of growth, but in the past year it has become more problematic as the rise in sales has slowed down and Walmart has admitted to expanding too hastily in China and Brazil.
In August, Walmart cut its sales forecast for global growth to between 2 per cent and 3 per cent for the year ending in January 2014, from 5 per cent to 6 per cent.
Rob Walton, Walmart’s chairman and one of the founder’s sons, said Mr McMillon was “uniquely positioned to lead our growing global company and to serve the changing customer, while remaining true to our culture and values”.
“He has broad experience, with successful senior leadership roles in all of Walmart’s business segments, and a deep understanding of the economic, social and technological trends shaping our world,” Mr Walton added.
Mr McMillon will take over as chief executive on February 1 next year.
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