Social movement scholarship has increasingly shown how continuous mobilization depends on collective memory construction. This article sets out to study this formative activity in a changing media landscape. It asks how activists navigate the temporal nexus of collective memory mediation. The empirical focus is on Brazil's Landless Rural Workers' Movement (MST), a well-established organization that since the early 1980s has communicated its collective memories on several media platforms. This article also demonstrates, through a corpus analysis of MST's internal newspaper, Jornal Sem Terra (1984-2014), and its Facebook page (2014-2019), how collective memories of rural violence serve various functions in these different media. The empirical study verifies the formative implication of rural violence for Brazil's landless movement, but also unveils notable differences between the newspaper and Facebook in this regard. Whereas Jornal Sem Terra employed a horizontal collective memory construction through contemporary documentation of ongoing and upcoming events, the Facebook posts primarily engaged in the vertical extraction of already established memories. In other words, the print media produced a narrative around collective memories of rural violence, and these memories were re-produced through digital media platforms. These empirical findings implicate that renewed methodologies are needed in future studies of social movements.