Tim was born to wealthy parents in Gotham City. His childhood was unusual, if happy. Born to wealthy parents, Tim grew up with all the toys he could ever want, and for Tim that meant computers. Over the years, he became quite an accomplished hacker. His other great hobby was a keen fascination with the exploits of the Batman. When Tim first heard of Batman, it was as an urban legend. But as he carefully observed news reports and such, he began to piece together information on the Bat and eventually on his sidekick, Robin, as well.
The boy's crowning moment of fanboy glory came when he deduced that Robin was Dick Grayson, since he had seen the Flying Graysons perform as a child, and in a rare bit of news footage, Robin was seen performing a stunt that only Dick Grayson could possibly execute. Once Batman's sidekick was unmasked in Tim's mind, it was easy to surmise that Bruce Wayne, Grayson's guardian, was the Batman. Tim might never have acted on this knowledge, had his family not been broken by a criminal attack.
Jack Drake, Tim's father, was a wealthy and influential businessman. When Tim was thirteen, a criminal group targeted Jack and his wife, Janet, for a kidnapping and ransom plot, taking them away to South America. Tim did the only thing he could think of: he went to Bruce Wayne for help. Confronted with a boy who had discovered his secret, Wayne agreed to find Tim's parents if Tim swore to keep silent about his and Dick's identities. Tim of course agreed, having never intended to tell anyone anyway.
Sadly, even as Tim was asking for Bruce's help, things had gone awry with the kidnappers and their victims. Jack's company refused to pay the money, and Janet was accidentally killed by a hot-headed terrorist. Thanks to Batman's intervention, Jack survived, but he was badly injured in the confrontation and left comatose. His wealth was more than enough to keep the bills paid and Tim taken care of, even arranging for him to live by himself under occasional supervision from his father's lawyer and a promise from neighbor Bruce Wayne that the boy would be looked after.
Though Tim never blamed Batman for what happened to his parents, he found himself settling into a deep depression. He was shaken from this state when Jason Todd was (to all appearances) killed in the line of duty as Robin. Tim watched the news as Batman went down a darker and darker path, and he finally sought out Dick Grayson to urge him to return to his role as Robin. Dick had come into his own as Nightwing by now and was not interested in returning to the role of junior partner, but Dick saw potential in Tim and conspired with Alfred to make Tim the new Robin. Nightwing began Tim's training himself, preparing him to impress Bruce enough to become Robin.
Bruce was against the idea at first, of course. He might never have been given a chance had it not been for Alfred. The faithful butler saw something in Timothy Drake, and whatever Alfred said to convince Bruce is known only to them, but soon enough Tim found himself going through a training regimen that would made boot camp look like a nice vacation. He lost all track of time, barely managing to keep up in school and spending every spare minute in training, and months passed. Finally, one fateful night, Bruce presented Tim with the newly recreated Robin costume and let him wear the mask for the first time. Robin was born again.
Even after Tim was accepted into the role of Robin, he was put through endless training. Under the auspices of a "study abroad" program, Bruce sent him to Paris for several months to train with Rahul Lama, master martial artist. This took a surprise turn, however, when Tim accidentally gained the attention of the infamous Lady Shiva. Shiva was impressed with Tim's budding skills, and she offered to train him personally. She was unimpressed by his choice of the non-lethal bo staff, but Shiva kept her word and furthered Tim's training.
By the time Robin returned to Gotham, he was ready for the role. Jack Drake remained in a coma. Since that time, Tim has devoted himself to making the role of Robin his own, all while balancing the life of his public identity and the trials of growing up without one's parents.
Several years passed, with Tim serving faithfully as Robin, increasing his skills and doing his best to keep his mentor and friend from slipping even further down the dark road he had set out upon. His father finally passed, but things seemed to settle into a routine until the coming of Darksied to the planet earth. Darksied killed the Batman, and Gotham city suddenly found itself besieged on all sides. An intense gang war, and Jason Todd donning the Bat-cowl and using it to kill, maim, and murder, prompted Tim to try and convince Nightwing to take up the Batman mantle but he refused. Even still, Tim kept fighting.
All seemed to be going well, until Robin drew the attention of Alpha, and was pulled into a chess match of galactic proportions.