Blackmar-Diemer Gambit
1.d4 d5 2.e4
The Blackmar-Diemer Gambit is a chess opening reached after 1.d4 d5 2.e4, catalogued under code D00 in the Encyclopaedia of Chess Openings (ECO).
The defining move e4 is chosen by White on move 2.
9 named continuations branch from this position, including the Blackmar Gambit and the Diemer-Rosenberg Attack.
What is the Blackmar-Diemer Gambit?
The Blackmar-Diemer Gambit is a chess opening that begins 1.d4 d5 2.e4 dxe4 3.Nc3 Nf6 4.f3. White sacrifices a pawn on move two and offers it again on move four to open the e- and f-files, develop every piece with tempo, and attack the black king before it can castle. It is the most famous of the 1.d4 gambits and the spiritual home of attacking club players.
Engines and grandmasters do not rate it: with accurate defense Black keeps the pawn or returns it for a comfortable position, and the gambit is almost never seen at master level. Over the board it is a different matter. The open lines, the rook on f1 staring at f7 and the quick Qe1-h4 and Bd3 setup produce attacks that arrive on move fifteen, and the number of club games decided by a Blackmar-Diemer sacrifice is enormous. Every 1...d5 player needs a prepared answer.
How to reach the Blackmar-Diemer Gambit
After 1.d4 d5 White plays 2.e4, and 2...dxe4 3.Nc3 Nf6 4.f3 is the Blackmar-Diemer proper. If Black accepts with 4...exf3 5.Nxf3, the defense is named by Black's fifth move: 5...e6 the Euwe, 5...Bg4 the Teichmann, 5...g6 the Bogoljubov, 5...c6 the Ziegler, 5...Bf5 the Gunderam. Black can decline with 4...Bf5, the Vienna Defense, 4...e3, the Langeheinicke, or refuse the whole thing earlier with 3...e5, the Lemberger Countergambit. The gambit also arises from the Scandinavian, 1.e4 d5 2.d4, and from 1.d4 Nf6 2.f3 d5 3.e4.
Pros and cons of the Blackmar-Diemer Gambit
Pros
- Every white piece develops with tempo and the f-file opens toward f7: the initiative is real and lasts for many moves.
- Thematic attacking patterns repeat: Qe1-h4, Bd3, Ne5, the rook lift Rf3-h3, and the sacrifice on f7 or h7.
- Unfamiliar for most 1...d5 players, who expect a Queen's Gambit and get a King's Gambit instead.
- Almost no drawish lines; White is playing for a win from move two.
Cons
- It is objectively unsound: a pawn for development that Black can return at the right moment for a comfortable game.
- The Euwe, Teichmann and Ziegler defenses are well known and neutralize the attack with precise moves.
- If the attack fails, White is a pawn down with a weakened king.
- Not a serious tournament weapon above club level.
Main variations of the Blackmar-Diemer Gambit
Blackmar-Diemer Gambit Accepted: Euwe Defense (5...e6)
1.d4 d5 2.e4 dxe4 3.Nc3 Nf6 4.f3 exf3 5.Nxf3 e6 6.Bg5 Be7 7.Bd3 Nbd7 8.O-O c5
The most solid defense: Black keeps the extra pawn, develops normally and prepares ...c5 to hit the center. White's attack with Bg5, Bd3, O-O and Qe1-h4 is dangerous but manageable, and the endgame after simplifications favors Black. Named for Max Euwe, who analyzed it in the 1930s; the line every gambiteer must be ready for.
Blackmar-Diemer Gambit Accepted: Teichmann Defense (5...Bg4)
1.d4 d5 2.e4 dxe4 3.Nc3 Nf6 4.f3 exf3 5.Nxf3 Bg4 6.h3 Bxf3 7.Qxf3 c6 8.Be3 e6
Black pins the knight and trades it, removing one of White's attacking pieces and keeping a rock-solid structure with ...c6 and ...e6. White gets the bishop pair and the queen on f3 aims at b7 and f7, so the initiative is not gone, but theory considers Black comfortable. The classical antidote and the most common defense at club level.
Blackmar-Diemer Gambit Accepted: Bogoljubov Defense (5...g6)
1.d4 d5 2.e4 dxe4 3.Nc3 Nf6 4.f3 exf3 5.Nxf3 g6 6.Bc4 Bg7 7.O-O O-O 8.Qe1 Nc6
Black fianchettoes the bishop and castles quickly, meeting White's attack with a solid king and counterplay on the long diagonal. It is the most ambitious defense and the one White players like least: after 8.Qe1 the attack with Qh4, Bh6 and Ng5 is coming, but ...Nc6, ...Bg4 and ...Nd5 give Black a full game. A favorite of players who know the Dragon or the Pirc.
Blackmar-Diemer Gambit Accepted: Ziegler Defense (5...c6)
1.d4 d5 2.e4 dxe4 3.Nc3 Nf6 4.f3 exf3 5.Nxf3 c6 6.Bc4 Bf5 7.O-O e6 8.Ne5 Bg6
Black plays ...c6 first, a Caro-Kann setup that keeps the bishop free to come to f5 and defends d5 and b7. It is solid and flexible, and after ...e6 and ...Be7 Black has kept the pawn with no weaknesses. White's typical try is Ne5 and g4 to harass the bishop, or the Qe1 and Qh4 plan; both need precise handling from Black.
Blackmar-Diemer Gambit Declined: Vienna Defense (4...Bf5)
1.d4 d5 2.e4 dxe4 3.Nc3 Nf6 4.f3 Bf5 5.fxe4 Nxe4 6.Qf3 Nd6 7.Bf4 e6
Black declines the second pawn and develops the bishop instead, returning the first pawn on White's terms. After 6.Qf3 the queen attacks both the knight and the b7-pawn, and Black must play accurately with ...Nd6 and ...e6 or ...Qc8. White gets active play for equality; Black gets a sound structure and avoids the open f-file.
Blackmar-Diemer Gambit Declined: Lemberger Countergambit (3...e5)
1.d4 d5 2.e4 dxe4 3.Nc3 e5 4.Nxe4 exd4 5.Bc4 Nc6 6.Nf3 Be7
Black returns the pawn at once with 3...e5, refusing to allow 4.f3 and steering the game into an open position with an isolated white d-pawn or a queen trade. It takes all the fun out of the gambit and is one of the best practical antidotes: the resulting positions are equal and White's attacking chances have evaporated.
How to play against the Blackmar-Diemer Gambit
Black has two reliable philosophies. The first is to accept and defend: after 4...exf3 5.Nxf3 play the Teichmann 5...Bg4, trading the f3-knight, or the Euwe 5...e6 followed by ...Be7, ...Nbd7 and ...c5; in both, develop fast, castle, and return the pawn with ...c5 or ...e5 when it eases the position. The second is to decline on your own terms: the Lemberger 3...e5 or the Vienna 4...Bf5 both hand the pawn back for a safe, equal game and deny White the open f-file. What loses is greed combined with slow development: keeping the pawn while the king sits on e8 is exactly what the gambit is designed to punish. Whatever you choose, watch the two standard sacrifices, Bxf7+ and Nxf7 with the queen on h4, and meet Qe1-h4 with ...h6 or ...g6 in time.
Plans for both sides
White's plan
Develop everything with tempo, castle kingside and put the queen on h4 via e1 or f3, the bishops on d3 and g5 or f4, and a knight on e5. Use the open f-file with Rf3-h3 or a sacrifice on f7, and play the attack before Black completes development; if Black consolidates, seek a favorable endgame from the bishop pair or accept equality.
Black's plan
Develop fast, castle early and neutralize the f-file: trade the f3-knight with ...Bg4, put the bishop on f5 or g4 before ...e6, and return the pawn with ...c5 or ...e5 when it gains time. Keep the king safe with ...h6 against Bg5 and Qh4, trade queens when possible, and head for the endgame where the extra pawn or the better structure counts.
History of the Blackmar-Diemer Gambit
The gambit began as the Blackmar Gambit, 1.d4 d5 2.e4 dxe4 3.f3, published by the American Armand Blackmar in 1882, which fails to 3...e5. The German master Emil Josef Diemer added 3.Nc3 Nf6 4.f3 in the 1930s and spent the rest of his life promoting the opening with missionary zeal, producing a devoted following, a newsletter and thousands of attacking games. It has never been accepted at master level, though Diemer, Gunderam and later Tim Sawyer analyzed it exhaustively, and it remains one of the most-played gambits at club level and online.
Blackmar-Diemer Gambit FAQ
Is the Blackmar-Diemer Gambit sound?
No. With accurate defense Black keeps the pawn or returns it for a comfortable game, which is why it is almost never seen at master level. It is dangerous in practice because the open lines and the fast development create attacks that unprepared players cannot handle.
How do you refute the Blackmar-Diemer Gambit?
Accept and play the Teichmann 5...Bg4 or the Euwe 5...e6 with fast development and a timely ...c5, or decline with the Lemberger 3...e5 or the Vienna 4...Bf5. In every case, develop quickly, castle, and return the pawn when it eases your position.
Is the Blackmar-Diemer Gambit good for beginners?
It teaches attacking chess and open-position tactics, which is valuable, but it loses a pawn by force and builds habits that fail against stronger players. It is best as an occasional weapon, not a main repertoire.
What is the difference between the Blackmar Gambit and the Blackmar-Diemer Gambit?
The original Blackmar Gambit is 1.d4 d5 2.e4 dxe4 3.f3, which is refuted by 3...e5. Diemer's improvement inserts 3.Nc3 Nf6 before 4.f3, which is the Blackmar-Diemer Gambit played today.
What is the ECO code for the Blackmar-Diemer Gambit?
The Blackmar-Diemer Gambit is classified under ECO D00, the code for 1.d4 d5 lines without an early c4.
Named variations
More ECO D00 openings
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