The Chechen was a foreign mob boss and drug dealer who controlled some organised crime in Gotham City.
After the League of Shadows' attempt to poison Gotham with fear toxin, the Scarecrow sold the substance to the Chechen. However it caused his customers to become nervous wrecks who didn't come back for more business, so the Chechen brought a junkie to the Scarecrow to show him what was happening. The Scarecrow was not sympathetic to the Chechen's problem, but before they could debate it their meeting was interrupted by Brian Douglas and other Batman impostors. The real Batman then arrived and apprehended the people at the meeting, before leaving.
The Chechen then met with Sal Maroni, Gambol and other mob leaders to discuss the problem of their money being targeted. Mr Lau proposed to have all the money in one place away from Gotham, but a man named the Joker arrived and said that the only way to keep it safe was to kill the Batman. The Chechen was interested in his proposition, and after Lau was kidnapped and brought back to Gotham the Chechen realised that the Joker was right. James Gordon then arrived and arrested the Chechen along with his men, thanks to Lau's testimony.
The Chechen and Maroni then hired the Joker to kill Batman, and he started killing other public figures in order to find Batman's identity. The Chechen later met with the Joker who had recovered all the mob's money as well as Lau, and he burned half of it. The Chechen told the Joker he was crazy, and the Joker responded by saying that the Chechen's men now worked for him. The Joker then cut the Chechen up and fed him to his own dogs.