The Gunpowder Conspiracy of 1605 was a plan to kill King James I of England and VI of Scotland . Other names for the plot are The Powder Treason or The Gunpowder Plot . The Gunpowder Plot of 1605 , in earlier centuries often called the Gunpowder Treason Plot , was a failed assassination attempt against King James I of England and VI of Scotland by a group of provincial English Catholics led by Robert Catesby .