Under his leadership, Kroger has positioned itself as a formidable competitor to Walmart, Amazon, and other grocery giants.

Kroger 's longtime leader Rodney McMullen abruptly resigned March 2 following a personal conduct probe initiated in February, ending a nearly 50-year career with the Cincinnati-based grocery giant. Here's what we know – and don't – about his career with the nation's largest traditional supermarket chain, and it's sudden end.

Here's what you should know about Kroger CEO Rodney McMullen, who resigned following "a board investigation of his personal conduct."