Historical records do not point to a single, universally accepted "earliest" mass poisoning from contaminated alcohol on June 27; rather, the archival evidence shows multiple notable episodes of mass harm from adulterated spirits across the 19th and early 20th centuries, often tied to industrial denaturants, methanol substitution, or toxic additives intended to stretch supplies. Documentation of these events varies by country, and surviving newspapers, coroner reports and municipal records sometimes disagree on dates, causes and death tolls. One frequently cited cluster of incidents took place in Europe and North America during the 19th century as commercial distillation and mass-market sales expanded. Adulteration—adding substances such as camphor, turpentine, opium, or low-cost alcohols—was widespread where regulation and quality-control were limited. Governments increasingly responded with licensing, inspection and later prohibition-era controls after high-profile poisoning episodes. A separate and well-documented pattern emerges in the early 20th century with methanol poisonings. Methanol (wood alcohol) is toxic to humans and was sometimes present in adulterated beverages either through deliberate substitution to increase potency or via improper distillation and denaturing practices. Several mass poisonings from methyl alcohol in Europe, Latin America and Asia in the 1920s and 1930s resulted in large numbers of deaths and permanent injuries (including blindness). These events prompted public-health campaigns and stricter regulation of spirits production. Because reporting standards, medical diagnostics and terminology evolved over time, contemporary accounts sometimes conflated causes—labeling deaths from alcoholic beverage-related poisoning, alcohol withdrawal, or infectious disease as linked to contaminated drinks. Local archival research is necessary to verify any claim tying a specific June 27 date to the earliest recorded mass poisoning from contaminated alcohol. Secondary sources that aggregate incidents can be useful starting points, but primary documents (newspaper archives, coroner inquests, municipal health reports) are required for precise dating and cause attribution. In short, while June 27 appears in some scattered reports related to alcohol poisonings, historians and public-health researchers treat the earliest instances of mass poisoning from contaminated alcoholic beverages as multiple, geographically dispersed events rather than a single, clearly dated first occurrence. Claims of a singular "earliest recorded" event should be treated cautiously and verified against primary archival records.