The study of Hong Kong identity has traditionally been positioned in a local–national dichotomy, where Hong Kong identity is viewed primarily as a local identity while the label of national identity is reserved for identification with the Chinese nation. Hong Kong nationalism, on the other hand, is generally considered a new phenomenon, the study of which has focused predominantly on the political activities in the post-handover period. Drawing on Partha Chatterjee's theory of anti-colonial nationalism, this paper seeks to broaden the understanding of Hong Kong nationalism by examining the nationalistic sentiments manifested during the Chinese language campaign (1964–1971). This paper draws on archival materials to shed light on the presence of anti-colonial nationalism in colonial Hong Kong, an aspect often overlooked or considered a mere extension of Chinese nationalism from mainland China. This paper also discusses the distinctions between anti-colonial nationalism in Hong Kong and Chinese nationalism, highlighting the intricate nature of the concept of Chineseness.