The defunct Diamond Shamrock gas station chain was named for a pair of two merged companies: the Cleveland-based Diamond Alkali, which produced soda ash, a key ingredient in glass production; and Pennsylvania-financed, Texas-based Shamrock Oil and Gas. John Sheerin, founder of the latter, named his company for the symbol of his native Ireland.

By 1995 there were 2,000 Diamond Shamrock stations, mostly in Texas, Louisiana, Colorado and New Mexico. In 2001 Valero acquired the chain, slowly and gradually changing every stations' brand signage till finishing in 2004 or 2005. Shortly afterwards, Valero expanded into brand new territory, notably the metro-Atlanta, Georgia market.

Valero Energy is a Fortune 500 international manufacturer and marketer of vehicular transportation fuels; other petrochemical products; and power, operating numerous namesake gas stations. It is headquartered in San Antonio, Texas, taking its name from part of the full name of the local historic mission, 'San Antonio de Valero'; the latter is a subset village of Salamanca in Castille and Leon, Spain. Throughout the United States and Canada, the company owns and operates 15 refineries, plus one in Wales.

The Alamo Bowl is a college football postseason game established in 1993. Valero began an annual continuous corporate sponsorship of the San Antonio-based event in 2007, thus as of that year till end of sponsorship (not yet) the contest has been billed as the Valero Alamo Bowl.

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