Latvian Gambit: Mason Countergambit

1.e4 e5 2.Nf3 f5 3.d4

ECO C40

The Latvian Gambit: Mason Countergambit is a chess opening line in the Latvian Gambit complex, reached after 1.e4 e5 2.Nf3 f5 3.d4.

It is catalogued under code C40 in the Encyclopaedia of Chess Openings (ECO).

The defining move d4 is chosen by White on move 3.

The Latvian Gambit: Mason Countergambit is a line of the Latvian Gambit. The Latvian Gambit is a chess opening that begins 1.e4 e5 2.Nf3 f5. Read the complete Latvian Gambit guide: what it is, how to reach it, its main variations, how to play against it, and its history.

More ECO C40 openings

• Elephant Gambit — 1.e4
• Gunderam Defense — 1.e4
• King's Knight Opening — 1.e4
• King's Pawn Game — 1.e4
• Latvian Gambit Accepted — 1.e4

Do you want to learn openings?

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• Catalan Opening
• King's Indian Defense with ...e5

Every chess term used here is defined in the chess terms glossary. Browse all opening courses or the full ECO code index.