Did Vikings Have Coffee and did they Drink it Hot: a study. My upcoming peer-reviewed paper in the Quarterly Journal of Norse Beveragology.
Abstract and Conclusion: While Vikings cannot be proven to have had coffee, documentary evidence strongly suggests that it would have been tepid at best, despite long held beliefs regarding flaming funerals, feasting at Valhalla, ad libitum et libatum. Archaeological evidence found in the house of Ole Sviggum which ibid lol suggests instead that early widespread adoption of Ovaltine snuffed out the nascent struggling nonprovable, possibly nonexistent warm beverage culture in Scandinavia and adjacent polities. Also, cooking with dragons breath crystals proved to be dangerous on longboat voyages to the extent they were discontinued entirely after the 8th century.