Founding of Tudeh Party of Iran, Mehr 10. This date commemorates the establishment of one of Iran’s influential political parties in the early 1940s. The Tudeh Party of Iran was founded in Mehr 1320 Jalali, following the abdication of Reza Shah, by a group of political activists and intellectuals. The party quickly gained influence among workers and students, focusing on political and social activism, especially labor rights and social justice. In its early years, the Tudeh Party played a significant role in Iran’s political and labor movements. Party members actively participated in strikes and protests, and the party published newspapers and statements supporting workers’ rights. At certain points, membership reached tens of thousands, making it a major force in the country’s political landscape. In the following decades, the Tudeh Party of Iran faced various restrictions and pressures from successive governments, and its activities underwent major changes throughout modern Iranian history. Nevertheless, the anniversary of its founding remains a milestone in the history of Iranian political parties and continues to attract the attention of researchers and those interested in the country’s political history. This observance was added to the Jalali calendar in 1321, following a decision by political activists to recognize the Tudeh Party’s significant impact on Iran’s social and political environment, and it is typically marked by recalling the party’s role in contemporary Iranian developments.