Mother's Day is observed on the last Sunday of May in several countries, including France and Sweden. The holiday was popularized in France during World War I when American soldiers sent letters to their mothers, leading to the creation of special postal cards by the Union Franco-Américaine. In 1918, the town of Lyon initiated its own celebration called “Journée Nationale des Mères de familles nombreuses,” awarding medals to mothers of large families, a tradition that continues today. The French government officially recognized the holiday in 1920, and by the 1950s, it had become commercialized. In Sweden, Mother's Day was introduced in 1919, but it was initially not widely celebrated due to perceptions of its commercial nature. Today, it is a day for families to honor mothers, often involving outdoor activities like flower picking.