Historical Events on May 18

23 significant historical events occurred on May 18. May 18 has seen various historical events throughout the centuries in areas like diplomacy, law, and sports. On this date in 1802, the Treaty of Amiens was signed during the Napoleonic Wars. In 1896, the Plessy v. Ferguson Supreme Court decision established the "separate but equal" doctrine. Additionally, notable motorsport events such as the 1952 Swiss Grand Prix and the 1969 Monaco Grand Prix also took place.