Question

When was the idea of Death Penalty Abolition first introduced?

Answer 1

Assuming you're referring to the idea that the Death Penalty should be made illegal (abolished), then this idea got its start all the way back in the Enlightenment, especially with Cesare Beccaria's 1767 essay, "On Crimes and Punishment".

Answer 2

The Idea of the Death Penalty took place in 1767.