This article is an analysis of African-American second-line parades in New Orleans and an autoethnography of the first major post-Katrina parade. At a moment of crisis, The Prince of Wales Social Aid and Pleasure Club raised funds to sponsor its annual parade and help rejuvenate local cultural spirit. The article defines a weekly second-line parade as a “mobile block party,” a four-hour and five-mile long community celebration that carnivalizes and colonizes the public sphere. For more than a century, brass bands have created a mobile musical platform for cultural affirmation, dance, style, self-expression, cooking, public grievance and ethnic customs. The club-sponsored second-line parade is the social institution that carries the Black cultural matrix which has always enculturated the city's jazz musicians, as shown in testimony from Louis Armstrong and Sidney Bechet. The article argues that the repression of these parades post-Katrina—and the lack of recognition for its cultural importance and continuity—constitutes “aesthetic racism.”