Hailed as a pioneer of the package delivery industry, billionaire founder and former CEO of FedEx Fred Smith has died at 80. 

According to a release shared by FedEx, Smith died on June 21, although the company did not specify the exact cause. In the release, current CEO Raj Subramaniam praised Smith — who stepped down as the head of the company in 2022 — as the "heart and soul" of the delivery giant. 

"He was a mentor to many and a source of inspiration to all," Subramaniam said. "He was also a proud father, grandfather, husband, Marine, and friend; please keep the entire Smith family in your thoughts and prayers during this difficult time."

A Marine Corps veteran who served two tours of duty in the Vietnam War, Smith is known for creating the "hub and spoke" distribution model, where goods are moved from a central hub to regional distribution centers for delivery. He first conceived the idea for FedEx in a paper he wrote as an undergraduate at Yale, where he proposed a model for overnight commercial air delivery. The paper received a C from Smith's professor.

FedEx began operating in 1973 on the back of $91 million in venture capital, but quickly accrued millions in debt due to rising fuel costs. Then in 1974, Smith took the last $5,000 in funds the company had left and bet it playing blackjack in Las Vegas, where he won $27,000, and ultimately bought enough time to raise another $11 million in funding to keep the company afloat. By 1976, FedEx's revenue had grown to $75 million, before it went public two years after that. The company topped $1 billion in revenue in 1983.