The analysis of land management, lineage, and family through the case study of early modern Spanish nobility from sixteenth to early nineteenth century is a major issue in recent historiography. It aims to shed light on how upper social classes arranged strategies to maintain their political and economic status. Rivalry and disputes between old factions and families were attached to the control and exercise of power. Blood, land management and honor were the main elements in these disputes. Honor, service to the crown, participation in the conquest and “pure” blood were the main features of Spanish nobility. Blood, Land and Power analyses the origins of the entailed-estate [mayorazgo] from medieval times to early modern period, as central elements that enable us to understand the socio-economic behavior of these families over generations. This long-durée chronology within a Braudelian methodology used in this research aims to show how strategies and family networks changed over time. This research is an example of a micro-history study of daily life and social practices of the main social actors of the elites and oligarchies in early modern Spain.