This chapter traces Singapore’s development as a global city since the introduction of rubber in Southeast Asia and the emergence of a plantation cluster directed to global export. While Singapore today is a quintessential example of a global city, this chapter historicises this concept by focusing on the entrepreneurs and corporate strategies behind the city’s growing connectivity in the first three decades of the twentieth century. As a result of the emergence of the rubber cluster, Singapore came to display the three elements that define a global city: service specialization, increased connectivity in transport and communication, and cultural prominence. The virtuous cycle expanding Singapore’s global reach was driven by the interaction among the city’s cosmopolitan trading community, the formalisation of cluster institutions under a supportive colonial government and multinationals’ strategies pursuing diversification and adaptation in times of crisis. The interrelation between clusters and global cities is an under-researched topic in both economic geography and the history of global capitalism. The Singapore case shows that clusters and global cities were typical ways of structuring foreign investment during the colonial period and underpinned the integration of Southeast Asia in the global economy before the 1940s.