Human sacrifice was practiced by many ancient cultures, as people would be ritually killed in order to please their higher power. The history of religious sacrifices mostly include a mass amount of blood shed, as ritual killing was a key component in the understanding of certain beliefs. In Christianity, salvation is made possible by the sacrificial death of Jesus Christ by crucifixion. This act was regarded by Christians as the "perfect" sacrifice, spilling his blood on the cross for the sins of the world. This story is taught in Christian schools, as well as often referred to through readings in religious churches.
There are two examples in this television series that had mass sacrificial deaths. In season one, Klaus sacrificed Elena's family and her loved ones in order to become a stronger vampire. He drew three circles in the ground, lights each circle on fire, and puts Elena, her aunt, and her love interest in each circle. Klaus uses this ritual to sacrifice Elena's aunt in an attempt to become the most powerful species on Earth.
There are two examples in this television series that had mass sacrificial deaths. In season one, Klaus sacrificed Elena's family and her loved ones in order to become a stronger vampire. He drew three circles in the ground, lights each circle on fire, and puts Elena, her aunt, and her love interest in each circle. Klaus uses this ritual to sacrifice Elena's aunt in an attempt to become the most powerful species on Earth.
In season four, Silas performs a triangle of sacrifices (killing hundreds of people) in order to become whole again. Further demonstrating the religious themes, one of the massacres happens in a church, where a pastor lights himself and other government officials of the city on fire. This video highlights each sacrificial death that is made to complete the triangle, resulting in three massacres of innocent witches, vampires, and humans.