The irruption of Persian-language blogging since 2001, known to its participants as Weblogistan, has been accompanied by enthusiastic claims that blogs are promoting previously nonexistent forms of expression in Iran. In the past few years, however, Iranian bloggers have faced increased scrutiny from Iranian authorities. This article explores what the political, offline consequences of online communication in Weblogistan tell us about the relationship among cyberspace, politics, and Islam in Iran. Drawing on archived blog entries, interviews, and Persian-language print media, we discuss the arrest of three bloggers in 2004 within the context of legal, religious, and cultural pressures exerted on Weblogistan. Revising McLuhan's “the medium is the message” by showing how local conditions affect the medium, we argue for a holistic understanding of Iranian blogging as (1) an emergent medium of communication (2) situated within a particular political context.