Pitirim Sorokin, a prominent sociologist, explored the socio-psychological dimensions of social change and revolution. His work often examined how societal crises and shifts in cultural values contribute to revolutionary upheavals. While other scholars like Ted Gurr also focused on the psychology of rebellion, Sorokin is frequently cited for his broad theoretical framework regarding the psychological and cultural triggers of revolutionary movements.

Samuel Huntington, in his analysis of political order and change, emphasized that social and political revolutions are not static events but dynamic, ongoing processes. He argued that the interplay between social forces and institutional responses creates a dialectical cycle of cause and effect. This perspective highlights the complexity of political development and the challenges of maintaining stability during periods of rapid social transformation.

Samuel Huntington, in his work 'Political Order in Changing Societies,' provides this specific definition of revolution. He emphasizes that revolution is not merely a change in leadership, but a total transformation of the social, political, and economic structures, as well as the underlying cultural values and myths that sustain the existing order.

While Nepal experienced significant political upheaval and a civil war, the transition from monarchy to a republic was largely achieved through the 'Jana Andolan II' (People's Movement) in 2006. This movement was characterized by widespread peaceful protests and strikes rather than an 'extremely violent mass uprising' in the traditional sense of a bloody revolution, leading to the eventual abolition of the monarchy.

The reunification of Germany occurred on October 3, 1990, following the collapse of the Berlin Wall in 1989. This historic event marked the end of the division between the German Democratic Republic (East) and the Federal Republic of Germany (West). It was a pivotal moment in the conclusion of the Cold War, signaling the integration of the former Soviet-aligned East into the democratic and capitalist framework of the West.

The period between the 1960s and the 1980s is widely recognized as the era of military authoritarianism in South America. During these decades, numerous countries in the region, including Brazil, Argentina, Chile, and Uruguay, experienced military coups that replaced democratic governments with authoritarian regimes. These regimes were characterized by the suspension of constitutional rights, political repression, and centralized control, lasting until the wave of democratization in the late 1980s.

Ted Robert Gurr is widely recognized for his seminal work 'Why Men Rebel,' which formalizes the theory of relative deprivation as a cause of political violence. Betty Nesvold also contributed significantly to the empirical testing and refinement of this theory in the context of political instability. Together, their research provides a framework for understanding how the gap between expectations and reality triggers social and political unrest.

Social disequilibrium refers to a state where the existing social structures, norms, and institutions fail to meet the needs or expectations of the population. When this imbalance becomes severe, it creates widespread frustration and alienation. Political theorists often argue that this systemic breakdown is the fundamental catalyst for revolutionary change, as the existing order loses its legitimacy and capacity to maintain social cohesion.

Crane Brinton, in his seminal work 'The Anatomy of Revolution', analyzed the English, American, French, and Russian revolutions. He identified common patterns and stages that these revolutionary movements traversed, providing a foundational framework for the sociological and political study of how revolutions occur and evolve over time.

Sigmund Neumann, often cited in political theory regarding the nature of revolutions, emphasized that revolutions are not merely changes in government but involve a total transformation of the underlying social, political, and cultural myths that sustain an order. This perspective highlights the psychological and ideological dimensions of revolutionary change, suggesting that a revolution succeeds only when the foundational beliefs of a society are fundamentally altered and replaced.