In order to understand the origins nitro, you must first journey across the pond, where the grand tradition of “cask ales” once dominated the local pub landscape.
With a cask ale, the brewery delivers a cask—or firkin—of still-fermenting beer to the pub. There, the publican is responsible for “conditioning” and finishing the beer prior to serving. A lot of things can go wrong along the way, and even when executed perfectly, cask ales have a short shelf life.
And so nitro beer was developed as a way to mimic the classic British cask ale experience. Nitrogenating a stable beer allows you to capture the similar head and mouthfeel of a cask ale while bulletproofing the process.