The central puzzle motivating this study is, why did the regime trajectories of India and Pakistan quickly diverge within a decade of their twin independences in 1947? Empirically, both India and Pakistan seemed equally unlikely to create stable and democratic regimes. Upon independence, both countries had emerged from an extended period of British colonial rule with low levels of economic development and broadly similar state institutions. Both states were governed as infant democracies under the same legal instrument until their sovereign constituent assemblies promulgated new constitutions. Both countries were beset by refugee crises, food insecurity, as well as security challenges. And both countries were governed by single dominant parties that were supported by multi-class coalitions and which had some experience governing at provincial levels prior to independence.;Yet, within a decade of their independence, the regime trajectories of India and Pakistan had radically diverged. India promulgated a constitution enshrining elections based on universal adult franchise, held national elections in the context of full civil and political liberties, and installed an elected chief executive. Pakistan's constitution-making process stalled, with its sovereign constituent assembly being twice dismissed by an autocratic chief executive, and with eight national administrations cycling through power with increasing rapidity until the military coup of 1958 formally ended its tentative democratic experiment. These different regime trajectories involved variation in both regime type as well as regime stability.;Drawing on elite interviews, an extensive analysis of colonial government records and party documentation, among other sources, I show how the most common explanations for democratization, such as low levels of economic development or high levels of inequality, cannot convincingly account for these divergent outcomes. Instead, I argue that two inter-related but causally independent variables provide the most compelling account of the divergent outcomes: the class compositions of their independence movements and the strength as well as content of their dominant political party at independence. Class interests had a powerful but historically conditioned impact on the type of post-independence political regime each independence movement was likely to establish. Because a landed aristocracy with disproportionate access to material resources and social status led its independence movement, Pakistan was very unlikely to create a post-independence regime which institutionalized opportunities for the redeployment of resources and status to other social groups, namely a democracy. Because an urban, educated middle class with a distinct material interest in creating more representative political institutions led its independence movement, India was substantially more likely to create a post-independence democracy.;Different social classes were motivated by their class interests to strategically create political parties of varying strength (along the dimensions of ideology, alliances, and organization) which directly impacted the likelihood of post-independence regime stability. First, the creation of a programmatic nationalism in India made its political party substantially more able to broker state-building compromises (providing for regime stability) while the content of Indian nationalism meant that its regime was likely to be a democracy. Second, while the pursuit of class interests led to an alliance between segments of the middle class in India, the same pursuit in Pakistan led to the creation of an alliance between a landed aristocracy and a peasant movement, an alliance with diametrically opposed redistributive interests. Stable, shared redistributive interests within its alliance meant that India's dominant political party was better able than Pakistan's to broker state-building compromises after independence, thus providing for regime stability . Third, while India's independence movement created a centralized and disciplined party organization, Pakistan's independence movement remained a top-heavy party organization with little institutional independence from its charismatic leader. Upon independence, the presence of a centralized, representative intra-party organization in India meant that its dominant political party was more able to quickly and decisively broker state-building compromises after independence, providing for regime stability.;This dissertation provides an original explanation for a puzzling divergence in regime outcome which remains insufficiently explained by extant scholarly literature on democratization. The argument developed here highlights that while regime outcomes hinge on redistributive conflicts, that social groups choose alliances, espouse ideologies, and build political institutions in response to a status quo distribution of power. Once created, these political institutions can affect, sometimes deeply, group understandings of whether democratization and regime stability is desirable.