448 - Blackbriar Thorn is born to the Druids of Cymru.
471 - 23-year-old Blackbriar Thorn becomes one of the singers of the Druids.
481 - 33-year-old Blackbriar Thorn assumes leadership of the Druids.
490 - 42-year-old Blackbriar Thorn watches as Arthur's rebellion against the Saxons begins.
491 - 43-year-old Blackbriar Thorn disproves of Jason Blood leaving the Druids to join Arthur's rebellion.
517 - 69-year-old Blackbriar Thorn joins the 2nd Shadowpact to stop Morgan Le Fay, but betrays Merlin to stop his influence on mankind, losing himself to natural magic in the process.
13 years ago - Blackbriar Thorn is unearthed. He begins trying to rebuild the world with Natural Magic, but is stopped by the Justice League.
8 years ago - Blackbriar Thorn is brought into the Injustice Society by Johnny Sorrow.
Blackbriar Thorn is a classic DC villain; at once one of the more memorable magic-wielding baddies AND one of a series of plant-based characters that populate the various corners of the world. Because he fits very easily into the larger tapestry of Arthurian Legend characters, we've expanded the role of both Thorn and of the Druids of Cymru, and in the process made him a more interesting and expansive character.
In fact, the bulk of his story is actually in the past. His modern incarnation really doesn't have as much to do other than to simply be one of the bad guys running around... badguying. There are a few vital moments, like his inclusion in Johnny Sorrow's Injustice Society, but perhaps his impact is simply in appearing at all. Jason Woodrue, best known as the Fluronic Man, is inspired in his plant hybrid work by the appearance of Blackbriar thorn, and of course his students include Alec Holland (Swamp Thing), Philip Sylvain (the scientist responsible for Black Orchid), and even Pamela Isley; Poison Ivy herself. So you could actually say that Thorn is responsible for quite a legacy of characters all on his own.