The Evans Gambit is characterised by the moves:
- 1. e4 e5
- 2. Nf3 Nc6
- 3. Bc4 Bc5
- 4. b4
The gambit is named after the Welsh sea Captain William Davies Evans, the first player known to have employed it. The first game with the opening is considered to be Evans -McDonnell, London 1827, although in that game a slightly different move order was tried (1. e4 e5 2. Nf3 Nc6 3. Bc4 Bc5 4. O-O d6 and only now 5. b4). The gambit became very popular shortly after that, being employed a number of times in the series of games between McDonnell and Louis de la Bourdonnais in 1834. Players such as Adolf Anderssen, Paul Morphy and Mikhail Chigorin subsequently took it up. After Emanuel Lasker's simplifying defense to the opening in a tournament in 1895, it was out of favor for much of the 20th century, although John Nunn and Jan Timman played some games with it in the late 1970s and early 1980s, and in the 1990s Garry Kasparov used it in a few of his games (notably a famous 25-move win against Viswanathan Anand in Riga, 1995), which prompted a brief revival of interest in it.
The Evans Gambit is an aggressive variant of the Giuoco Piano, which normally continues with the positional moves 4. c3 or 4. d3. The idea behind the move 4. b4 is to give up a pawn in order to secure a strong centre and bear down on Black's weak-point, f7. Ideas based on Ba3, preventing black from castling, are also often in the air. According to Reuben Fine, the Evans poses a challenge for Black since the usual defenses (play ...d6 and/or give back the gambit pawn) are more difficult to pull off than with other gambits.
The most obvious and most usual way for Black to meet the gambit is to accept it with 4... Bxb4, after which White plays 5. c3 and Black usually follows up with 5... Ba5 (5... Be7 and, less often 5... Bc5 and 5... Bd6, the Stone Ware Variation, are also played). White usually follows up with 6. d4. Emanuel Lasker's line is 4... Bxb4 5. c3 Ba5 6. d4 d6 7.0-0 Bb6 8.dxe5 dxe5 9.Qxd8+ Nxd8 10.Nxe5 Be6. This variation takes the sting out of White's attack by returning the gambit pawn and exchanging queens, and according to Fine, the resulting simplified position "is psychologically depressing for the gambit player" whose intent is usually an aggressive attack.
Alternatively the gambit can be declined with 4... Bb6, when 5. a4 a6 is the normal continuation. But due to the loss of tempo involved, most commentators consider declining the Evans Gambit to be less strong than accepting it, then giving up the pawn at a later stage. Also, Black can play the rare Countergambit Variation (4... d5), but this is thought to be rather dubious.
The famous Evergreen game started off with the Evans Gambit.
The Encyclopaedia of Chess Openings has two codes for the Evans Gambit, C51 and C52.
- C51: 1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.b4
- C52: 1.e4 e5 2.Nf3 Nc6 3.Bc4 Bc5 4.b4 Bxb4 5.c3 Ba5
After 4. b4 Bxb4 5. c3, the Bishop must move or be captured. The common retreats are listed here, with the good and bad side of each:
5... Ba5 This is the so called Normal Variation. This is Black's most popular retreat. It gets out of the way of White's central pawns, and pins the c3 pawn if White plays 6. d4. The bad side of the Normal Variation, however, is it takes away the a5 square for the Black Knight. In the Evans Gambit, the Nc6-a5 move is crucial in most variations, especially if White has a Bishop at c4 and a Queen at b3. Because of this, Black almost always moves the Bishop to b6, to allow ... Na5.
5... Bc5 This is the second most popular retreat, with White scoring better than in the Normal Variation. This is often played by people unfamiliar with the Evans Gambit, but is arguably not as good as 5... Ba5, because White can open up the center with 6. d4.
5...Be7 This has often been considered one of the "safer" retreats, and has been played by Anand. After 6.d4 Na5, White can attempt to maintain an initiative with 7.Be2 as played by Kasparov, or immediately recapture the pawn with 7.Nxe5.
5...Bd6 This is called the Stone-Ware defense after Henry Nathan Stone and Preston Ware. The move reinforces the e5-pawn and been played by several grandmasters such as Andrei Volokitin, Alexander Grischuk and Loek van Wely.