The King's Gambit is an agressive opening for white, where sharp tactics and sacrifices tend to dominate play.  White weakens his own king's position with the idea of gaining a lead in development, a central pawn majority, and control of a half open f-file.

The King's Gambit was one of the most popular openings for a long time.  It took two blows to it's popularity, however.  The first was the rise of a more defensive and positional style of chess, which was lothe to create any weaknesses in it's own position, and which therefore shied away from the King's Gambit.  The second was an article by Bobby Fischer, "A Bust to the King's Gambit," which claimed that 3...d6 was the refutation of the King's Gambit.  The statistics have not supported that claim, however.  On this site's database, for instance, white has scored better than 55% from 832 games (49.04% wins, and 13.82%, see www.chess.com/opening/eco/C34_Kings_Gambit_Accepted_Fischer_Defense).  Hardly a terrible record for white, yet the fact that Bobby Fischer, arguably the strongest player of the last century, believed it to be refuted turned a lot of players off to the opening.

The King's Gambit is, however, an opening that will train your eye for tactics, and give you a feel for what can be accomplished with a material sacrifice.  Since these are probably the most important thing for beginning players to work on, the opening is well worth playing.  This article is designed to give a basic understanding of the principles involved.

The Classical center

 

 

Take a careful look at this diagram.  Memorize it.  A lot of opening theory is based around this ideal.  Notice how much control white has over the central squares.  d4 and e4 are both occupied by protected pawns.  d5 and e5 are both attacked three times!  White's king has gotten to safety, and the rook on f1 is somewhat active.  White has a large spacial advantage.

The goal of much of opening theory is to be able to set up the clasical center or to prevent you opponent from setting it up.  In light of this, 2.f4 makes perfect sense.  1.e4 is an attempt to begin setting up a center, and 1...e5 both begins setting up black's center and discouraging d4.  2.f4 offers up a pawn to strip away the e5 pawn. 

 

White now has two goals, or sequences of moves that he wants to play.

1. white wants to play d4, followed by Bxf4.  This sets up the pawn duo on e4 and d4, and moves the bishop to its ideal square while capturing a piece which has moved twice, a significant gain in time.

2.  white wants to play Nf3 and Bc4, followed by 0-0.  Nf3 removes the threat of Qh4+ (which would exploit white's missing f pawn), places the bishop on its ideal square (where it attacks the f7 pawn), moves the king to safety, and moves the rook to the half open file (where it adds presure to the f-file).

The interplay of these two goals gives us a new ideal that white is shooting for.

Notice the similarities between this diagram and the clasical center.  White is only one move away from achieving the clasical center, minus the f-pawn.  And, in fact, once white has castled short, the absence of the f-pawn is actually more of a benefit than a weakness, since his rook controls the half open file.  Not surprisingly, many of black's attacks will be launched down the f-file or by targeting the f7 square.

Notice also that the queen's knight is the least important minor piece to develop for white.  This is because every other developing move serves two purposes.  d4 sets up the pawn duo in the center while opening up for the bishop to recapture on f4.  Bxf4 develops the bishop to its ideal square while regaining the pawn.  Nf3 develops the knight to its ideal square while preventing Qh4+ and preparing to castle, and Bc4 develops the bishop to its ideal square while adding pressure to f7 and preparing to castle.  Nc3 merely develops a piece, so unless you can do it while threatening something or defending against a threat, it is far less urgent than the other moves.

Of course, black also gets to move.  Logically, black's goal is to prevent white from achieving his plans.  There are three possible ways that black can frustrate white's goals.

1.  Black can try to hold onto the pawn on f4, thus preventing white from develoning his c1 bishop with a capture and limiting the effectiveness of the white rook on f1 by blocking access to f7.  This is usually done by playing ...g5, or by preventing d4.  The downside of this is that ...g5 weakens the black kingside, and preventing d4 is harder than it sounds.

2.  Black can attempt to make it impossible for white to castle, either via Qh4+ (before white plays Nf3) which forces the king to move (since g3 fails to fxg3, and the rook will fall) or else via placing the bishop on c5 and exploiting the hole on f2 (more common in the King's Gambit declined, in light of d4! chasing the bishop away and achieving white's ideal break with tempo)

3.  Black can attempt to return the pawn at some later point in an attempt to catch up in development.

Here is an example game, where black made a few errors early on that white exploited.

 

 

 

 

 

 

 

 

This game was posted a few days ago, but there I focussed on the tactics rather than the opening with my commentary.

 

 

 

I hope that these ideas are helpful, both for those who want to play the King's Gambit, and also for those who will have to defend against it.

Good luck!