Northern Irish Garth Ennis began writing comics at 19, starting with the Troubled Souls series that was published in British anthology Crisis in 1989. Troubled Souls was followed by a sequel, For a Few Troubles More that introduced characters Dougie and Ivor who would later star in their own American comics series, Dicks.
He has also done work in the Top Cow/Marc Silvestri title "The Darkness" and written many limited series like "Fury" covering Marvel's Nick Fury character, Thor: The Vikings, and more recently Ghost Rider: Trail of Tears.
The subject matter of his work is usually of an adult nature, containing extensive violence, profanity, and dark humor. Ennis' writer-owned title, "The Boys," was pulled by Wildstorm (a division of DC) after 6 issues due to its graphic content. The title has now resumed publication by Dynamite Entertainment, including the release of a trade paperback containing the 1st 6 issues.
Through a trend of Ennis' wherein, if he is leaving a title that will continue without him or potentially be revived without him at a later date, if he doesn't own the characters but if there are any characters in the book that he created or had a major part in shaping, he doesn't like to let other writers play with his toys, so he offs the characters that were his. This was done to almost all characters at the end of "Hitman" and to pretty much every character created by Ennis during his run on "Hellblazer" when he left the book.
Ennis is one of very few creators who published a significant amount of work through DC's Vertigo imprint in the form of miniseries in the mid 90's where the majority of their work in that form from that period is still in print.
Until very recently Ennis was head Writer for Marvel's premier vigilante title, The Punisher. He is probably the most important writer for the character, as he explored every aspect of Frank Castle during his eight year run. He wrote The Punisher for Marvel Knights first in 2000. This title had a very tongue in cheek tone, but there were a few excellent stories. In 2004, he elaborated on his previous stories by writing The Punisher MAX series. These stories had a very serious tone, and were exemplified by realism and violence. It can be said he wrote some of the greatest stories of The Punisher, among them The End, The Cell, The Tyger, Widowmaker, and what many call the single greatest tale of The Punisher ever, BORN, in which he looks over The Punisher's Vietnam days, and how Frank Castle became the vengeful killer. He wrote it in 2003.
Much of Ennis' current work is through Avatar Press where he can get away with even more of his trademarked brand of merry depravity than even Vertigo ever let him get away with. He also does much work for Dynamite, the publisher who rescued The Boys. In addition to The Boys, Ennis has created a series of war minis under the title "Battlefields", and, most recently, a new miniseries called "Jennifer Blood" with which he admits he's getting a bit of the ultra violence and lighter side of his pitch-black humor out of his system, that's been absent from much of his work over the past few years.