A caudillo ( kaw-DEE(L)-yoh, kow-, Spanish: [kawˈðiʎo]; Old Spanish: cabdillo, from Latin capitellum, diminutive of caput "head") is a type of personalist leader wielding military and political power. There is no precise English translation of caudillo, though it is often used interchangeably with "warlord" and "strongman". The term is historically associated with Spain, and with Hispanic America after virtually all of the region won independence in the early nineteenth century.

The roots of caudillismo may be tied to the framework of rule in medieval and early modern Spain during the Reconquest from the Moors. Spanish conquistadors such as Hernán Cortés and Francisco Pizarro exhibit characteristics of the caudillo, being successful military leaders, having mutual reliance of the leader and their supporters, and rewarding them for their loyalty. During the colonial era, the Spanish crown asserted its power and established a plethora of bureaucratic institutions that prevented personalist rule. Historian John Lynch argues that the rise of caudillos in Spanish America is rooted not in the distant Spanish past but in the immediate context of the Spanish American wars of independence. Those wars overthrew colonial rule and left a power vacuum in the early nineteenth century. Caudillos were very influential in the history of Spanish America and have a legacy that has influenced political movements in the modern era.

The term is often used pejoratively by critics of a regime. However, Spain's General Francisco Franco (1936–1975) proudly took the title as his own during and after his military overthrow of the Second Spanish Republic in the Spanish Civil War (1936–39). Spanish censors during his rule attacked publishers who applied the term to Hispanic American strongmen. Caudillos' exercise of power is a form considered authoritarian. Most societies have had personalist leaders at times, but Hispanic America has had many more, the majority of whom were not self-described caudillos. However, scholars have applied the term to a variety of Hispanic American leaders.