This chapter emphasizes how understanding the impact of communications can help the interdisciplinary thrust to integrate sociology with history and international relations (IR). It discusses a global history of how communications affected populations around the world, which demonstrates why they played a key role in differentiation. It also talks about how colonialism helped to entrench imperial rule for decades before anticolonial activists used some Western communications systems in their favour. The chapter assesses the contemporary situation, where American-owned social media companies appeared to be the drivers of democratic social change during the Arab Spring of 2011, but now seem to foster conspiracy-theory-driven violence. It presents nine different forms of impact, subdivided into cultural, economic, political, and environmental clusters that illustrate the myriad uneven global effects of communications over time and space.