The Candlelight Movement of 2016 and 2017 that successfully called for president Park Geun-hye to step down is among the largest social movements in South Korean history. This movement attracted millions of participants over a sustained period of time, while maintaining strikingly peaceful demonstrations that ultimately achieved their goal. This essay looks at the role of the Internet and new media in fostering a new generation of activists and laying the foundation for a successful social mobilisation.