The majority of authoritarian regimes rely on a political party to govern, and studies show that political parties contribute to the political survival of dictators. However, there is a considerable variation on organizational developments of such ruling parties. Why do some authoritarian regimes institutionalize their ruling party and penetrate society through party organizations? Why do some dictators build up local party branches as linkage to the masses? I argue that the initial condition when a dictator comes to power determines the ruling strategies he will choose. The ruler needs to establish party organizations to control the masses when he subjectively thinks the threat to regime survival mainly comes from internal threats, especially the masses. However, if there exists a foreign enemy with territorial conflicts, the leader must direct resources to the coercive institutions, especially the military, to defend against threats. This study uses a cross-national dataset, covering all of dictators from 1950-2008, to illustrate the causes and consequences of ruling party institutionalization at the local level, accompanied by comparative historical studies of two country-pairs, Taiwan and South Korea, and Indonesia and the Philippines. Empirical evidence corroborates the hypotheses that external enemies with territorial threats impedes party institutionalization, while higher levels of religious polarization prompt the leader to develop party's local organizations. Also, party institutionalization at the local level significantly prolongs political survival of dictators, because it helps leaders to collect essential information for the ruling and enhances legitimacy.