This article explores how political calendars and shared martyrology provided important markers of identity and symbolic tools for political mobilization in Mandate Palestine. The dates on the emerging Palestinian calendar grew out of the politicization and nationalization of traditional holy days, as well as the commemoration of politically significant events of the period, including those involving local Palestinian martyrs. Commemorative events were especially important for the advancement of Palestinian particularism, which could not rely on a distinct language and culture or a common religion. Although the Palestinian elite was well aware of the importance of these markers to identity formation, its ability to nurture them was limited by institutional weakness, lack of political sovereignty, and British antagonism to such events.