Korea and Japan, shaped by the geopolitical condition of close proximity, have long been connected by the constant movement and intermingling of objects, events, and people. The music industries of the two countries have likewise crossed, reinforced, and eroded boundaries, while long histories and entrenched perceptions have often surfaced in the form of prohibition and exclusion. How, then, did music industries once divided by “openness and prohibition, enthusiasm and antagonism, admiration and competition” come to reference one another and increasingly intermingle, culminating in scenes today in which K-pop idols perform Japanese songs that were once subject to restriction and exclusion in Korea? And at what points in this process did the public emerge as a newly significant force? To address these questions, A History of Korean and Japanese Popular Music: From the Age of Kayōkyoku to the Era of K-pop traces seventy years of popular music history. It introduces representative songs and musicians that illuminate major shifts in popular music: from the normalization of diplomatic relations between Korea and Japan in 1965 and Japan’s rise as the world’s second-largest music market in the 1970s, through the transition of the Japanese music industry from a system centered on kayōkyoku to J-pop in the 1980s; the growing divergence between Korean and Japanese popular music in the 1990s; and, finally, the full emergence of K-pop with the Korean Wave boom from the 2000s through around 2020. The program also examines how the public, increasingly visible as both consumers and producers, influenced the music industry in each period, thereby tracing popular desires as they emerged across the interconnected fields of politics, society, and culture. The history of music is, in this sense, inseparable from the history of the public as shaped by political, social, and cultural forces. To read music history is also to read the desires of the public in the here and now.