Rose City Antifa (RCA) is an anti-fascist group founded 2007 in Portland, Oregon.^[1] It has been called the oldest active antifa group in the US.^[2][3]

Rose City Antifa has clashed with law enforcement officials and supporters of the Donald Trump presidency following the 2016 presidential election.^[4] Prior to a Patriot Prayer rally, the group released a statement saying they would be "unapologetic" over the use of "physical militancy".^[5] The group has organized opposition to Patriot Prayer rallies in Portland.^[6] According to one of its leaders, the group concentrates on "outing" people who they believe are neo-Nazis.^[7][8]

According to Alexander Reid Ross, an academic specializing in anti-fascist movements, RCA grew out of the group Anti-Racist Action, which first appeared in 1987, and through RCA "the European and American models were sort of synthesized and the current model of Antifa in the US was developed".^[9]

On 30 June 2019, the practice of throwing milkshakes at individuals supposedly became violent for the first time, as Portland Police tweeted that they had received a report that some milkshake had contained quick-drying cement. No evidence for this claim has been presented and it is unknown who is alleged to have thrown or been targeted by the alleged concrete-containing milkshake.^[10][11][12] Andy Ngo, a journalist for Quillette who was beaten and sprayed with silly string by members of Antifa, also had a milkshake thrown at him.^[13][14]