1982 (age 63)
Dionysus Yaxley (1919 – 1982) was a pure-blood wizard, first son of Terence Yaxley and Anabetteh Yaxley (née Warrington), brother of Tiberius Yaxley, husband of Ferula Abbott and father of Emma, Helius and Furius Yaxley II. He was educated at Hogwarts from 1930 until 1938, having been sorted to the Slytherin House. His marriage with Ferula Abbott (Hannah Abbott's great-grandaunt) was purely a facade to preserve the pure blood of Yaxley hegemony and to allow children to Dionysius to ensure the Yaxley line did not go extinct.
In his time as a student, Dionysius earned honors as Student Model, "Junior Wizard's Chess Champion", Prefect, Head Boy and "Specialist Removal of Bubotuber's Pus." Many questioned why a student as bright as Yaxley has not been selected for Ravenclaw, but the explanation was simple. Dionysus, like his brother Tiberius (but not the fool Tiberius was), was ambitious and wanted to be the head of the wizarding world more than anything. For many it was dark, macabre, but when it valued the interests of others Dionysus was the genius of the new world.
Dionysius at the time was slated as the one who could unseat Nobby Leach as Minister for Magic. However, Dionysius followed the path of Death Eater, a faithful follower of Lord Voldemort. As his death occurred in 1982, it is possible that he died in the efforts to round up Death Eaters after the supposed death of Voldemort, and not by natural causes.