The Chigorin variation begins with 1. e4 e6 2. Qe2. While it may look odd to move the queen one square to block in the bishop, databases show that the Chigorin is one of the most successful variations against the French!The queen move has two purposes. First, white temporarily restrains black from advancing to d5 by pinning the e pawn. If white captures on d5, black would have to recapture with the queen. Second, white’s long term plan is to enter a line of King’s Indian Attack in which the queen is well-placed on e2.
The most common response for black, and the one recommended by theory, is 2. ...c5. This typically leads to well-trodden lines of the King's Indian Attack. Alternatives like 2. ...Be7 often simply transpose.
Another option for black is to move ...e5, either immediately or after ...Nc6. Black gives up a tempo, relying on the white queen being misplaced on e2. White can respond in several ways, the most exciting being an improved version of the King's Gambit after 3. f4!?
Because the opening often leads to a KIA formation, many of the main line games are included in the separate collection "King's Indian Attack with Qe2."