Today is the birthday of John the Fearless (May 28, 1371–September 10, 1419). He was “also known as John of Valois and John I of Burgundy, [and] was Duke of Burgundy from 1404 to 1419. He was a member of the Burgundian branch of the Valois Dynasty. For a period of time, he served as Regent of France on behalf of his first cousin King Charles VI of France, who suffered from severe mental illness.”

Here’s another short biography from the University of Ohio’s eHistory:

Philip the Good John earned the moniker Fearless during a crusade he attempted to lead against the Turks in Nikopol in 1396. The Crusaders were defeated and John was captured. He was ransomed a year later. At the age of 33 he succeeded his father as duke. During the battle of Agincourt he was noticeably missing. During the next few years he negotiated with Henry V but no firm alliance was ever struck. He was assassinated in 1419 by partisans of the the dauphin Charles (later King Charles VII) during a negotiation session.

The origin of Gambrinus is “most widely believed to be John the Fearless (1371–1419), who some also believe to be the inventor of hopped malt beer.”

This speculation is written by Hugh Evans for the Homebrew Emporium:

The second historical figure who may have been mythologized into Gambrinus was John the Fearless (1371-1419), Duke of Burgundy. While Burgundy was known then as now more for wine than beer, it too produced a lot of ale. More surprising, John the Fearless is credited with being influential in the introduction of hops to European brewing. Prior to the use of hops, European brewers used a collection of herbs called Gruit to provide a bitter component to beer, as well as to help stabilize it. John Duke of Burgundy appears to have encouraged brewers in his fiefdoms to switch to using hops during his reign, reinforcing a trend that was already spreading across the continent.

And this is from the Lord of the Drinks:

An alternative name is John the Fearless (1371-1419), who was Duke of Burgundy. This John was also quite fond of long drinking sessions. Plus under his reign the use of hops in beer was legalized in several areas in Belgium. Since the mythical Gambrinus is said to have introduced hops, this could be a clear indication. Although hops was already used in nearby areas before John, and all together it took about 500 years before this ingredient had found its way to all corners of “the Lowlands”.