Short answers, pulled from the story.
Robert Devereux 2nd Earl of Essex was born on the 10th of November 1565 at Netherwood in Herefordshire. He was the eldest son of Walter Devereux and Lettice Knollys and became a ward of the Crown after his father died in September 1576.
Robert Devereux 2nd Earl of Essex was appointed colonel-general of the English cavalry in September 1585. He accompanied his stepfather the Earl of Leicester on a military apprenticeship in the Spanish Netherlands that transformed him from a courtier into a war hero.
Robert Devereux 2nd Earl of Essex returned to England on the 24th of September 1599 without orders because his campaign in Ireland failed to defeat Hugh O'Neill. He deserted his post as Lord Deputy of Ireland after his numbers dwindled to 4,500 and he refused to engage the enemy.
Robert Devereux 2nd Earl of Essex marched out of Essex House on the morning of the 8th of February 1601 to force an audience with Queen Elizabeth I. His attempt to enter London failed when Crown forces under John Leveson placed a barrier at Ludgate Hill and besieged his home.
Robert Devereux 2nd Earl of Essex was beheaded by executioner Thomas Derrick on the morning of the 25th of February 1601 within a courtyard of the Tower of London. The execution took three strokes and Walter Raleigh witnessed the event while Essex begged for a private execution rather than a public one.