Falkbeer Countergambit

2...d5 is the most common way to decline the king's gambit (at least, for the moment: Black often takes the f-pawn later).

White has the choice of two centre pawns they may take, though 3. fxe5?? is a blunder as 3...Qh4+! 4. g3 Qxe4+ 5. Qe2 Qxh1 is most embarrassing.

3. exd5 is the main move, leading to a scramble for control of the d5, e4, and e5 squares. Black's traditional idea (called the Staunton line) is 3...e4, but more common today is 3...exf4 4. Nf3, transposing into the modern line of the king's gambit accepted, as if they had played 2...exf4 3. Nf3 d5 4. exd5.

3. Nf3, the Blackburne attack, postpones taking in the centre to develop the knight. This controls the h4 square, ending with the threat of ...Qh4+, and if 3...dxe4 (attacking the knight) 4. Nxe5!. After 3...exf4 4. exd4 this transposes. Alternatively, 3...Bg4 4. Be2 exf4 5. exd5 Bxf3 6. Bxf3 Qh4+ 7. Kf1= and Black equalises.

Other lines include:

• 3. d4?, the Hinrichsen gambit.
• 3. Nc3?!, the Milner-Barry variation.

The earliest recorded appearance of this countergambit comes from the games of 17th century chess player Gioachino Greco, who recorded the following miniature (Greco as White): 3. exd5 Qxd5 4. Nc3 Qe6 5. Nf3 exf4+ 6. Kf2 Bc5+ 7. d4 Bd6?? (...Be7 is better) 8. Bb5+ Kf8 9. Re1 Qf5?? (Black must give up the queen or is lost) 10. Re8# 1-0.^[1][2]

Ernst Falkbeer (1819―1885) was an Austrian chess master who played 2...d5 against Adolf Anderssen in 1851, with the continuation 3. exd5 e4.^[3] In 1905, Frank Marshall (1877―1944) introduced the continuation 3...c6.^[4]

1. e4 e5 2. f4 d5

Wikipedia has related information at King's Gambit.

• Kasparov, Garry, & Keene, Raymond 1989 Batsford chess openings 2. ISBN 0-8050-3409-9.

• 365Chess. 1. e4 e5 2. f4 d5
• chessgames. 1. e4 e5 2. f4 d5