Luis Carrero Blanco served as the Prime Minister of Spain under Francisco Franco and was considered one of Franco's most trusted allies. His tenure began in 1973 and was marked by significant political tension within Spain. The Basque separatist group ETA, established in 1959, aimed to promote Basque nationalism and achieve independence from Spain. The assassination on December 20, 1973, was a culmination of years of escalating violence between the Spanish state and ETA. The attack was meticulously planned, involving explosives placed beneath the street in Madrid where Blanco's car would pass. When the bomb detonated, it propelled his car onto a nearby rooftop, killing him and two other individuals on impact.The assassination was a dramatic escalation in ETA's campaign against the Franco regime and sent shockwaves throughout the Spanish political landscape. It demonstrated ETA's capabilities and willingness to target high-ranking officials, effectively undermining the regime’s authority. Following Blanco's death, the Spanish government initiated a crackdown on ETA, leading to increased repression and violence which ultimately intensified the conflict between the Spanish state and Basque separatists. This event marked a turning point in the struggle, as it signaled the fragility of the Francoist government and paved the way for political change within Spain.