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Classic game replay

Adolf Anderssen vs Johann Jacob Loewenthal, 1851

This replay preserves the complete 39-ply score of Anderssen playing White across 20 numbered moves. The board can be advanced one ply at a time; the notes stick to observable board changes rather than guessing at the players’ intentions.

On this page
  1. Practice positions
  2. Replay with move-by-move board facts
  3. PGN
  4. Sources and checking
  5. Continue with another game
White
Adolf Anderssen
Black
Johann Jacob Loewenthal
Event
London m9
Year
1851
Result
1-0
Opening
C33 King's Gambit Accepted: Bishop's Gambit, Kieseritzky Gambit

Opening reference: King's Gambit Accepted: Bishop's Gambit, Kieseritzky Gambit (C33).

In this game, 20 half-moves are labelled opening, 19 middlegame and 0 endgame. The score contains 11 captures and 3 checks or mates; before a recorded move, the position offered a median of 34 legal choices. The source score ends after 20.Qh4+ with the recorded result 1-0. Its termination tag was not retained, so this record does not infer whether the game ended by resignation, time or another cause.

Practice positions

The daily trainer uses a short set of positions from this complete score. Each link goes to the exact half-move rather than only the numbered move.

  1. 8.Nf3 — Develop the knight8.Nf3 was a leading choice in the fixed engine check.
  2. 15.Rxh8+ — Capture with check on h815.Rxh8+ was a leading choice in the fixed engine check.
  3. 20.Qh4+ — A forcing check20.Qh4+ was a leading choice in the fixed engine check.

Replay with move-by-move board facts

The board, fact panel and transcript use the same legal score. “Fixed engine check” means Stockfish 17.1, one thread, a fixed 25,000-node search and 3 candidate lines. It compares moves under one reproducible setting; it does not claim to reconstruct a player’s thoughts.

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Adolf Anderssen vs Johann Jacob Loewenthal, 1851

Start position

Use Previous and Next on the board, or select a move in the transcript. The board fact and fixed engine check remain visible until you choose another move.

Opening · 1.e4 to 10...Nf5

  1. 1.e4 Claim central space

    Board fact: White moves the pawn from e2 to e4; from there it controls d5 and f5.

    Fixed engine check: Ranked first · e4 e5 Nf3 Nc6.

  2. 1...e5 Claim central space

    Board fact: Black moves the pawn from e7 to e5; from there it controls d4 and f4.

    Fixed engine check: Ranked first · e5 Nf3 Nc6 d4.

  3. 2.f4 Change the pawn structure

    Board fact: White moves the pawn from f2 to f4; the move changes the central pawn contact; from f4 it attacks Black's pawn on e5.

    Fixed engine check: Playable; Nf3 ranked higher · f4 exf4.

  4. 2...exf4 Exchange on f4

    Board fact: Black's pawn takes the pawn on f4; the move changes the central pawn contact; Black accepts doubled pawns on the f-file; black is ahead by 1 conventional material point after the capture.

    Fixed engine check: Ranked first · exf4 Nf3 d5 exd5.

  5. 3.Bc4 Develop the bishop

    Board fact: White develops the bishop from f1 to c4; from c4 it attacks Black's pawn on f7.

    Fixed engine check: Ranked first · Bc4 Qh4+ Kf1 d5.

  6. 3...b5 Create pressure on c4

    Board fact: Black moves the pawn from b7 to b5; from b5 it attacks White's bishop on c4.

    Fixed engine check: Playable; d5 ranked higher · b5 Bxb5.

  7. 4.Bxb5 Exchange on b5

    Board fact: White's bishop takes the pawn on b5; from b5 it attacks Black's pawn on d7; material is level after the capture.

    Fixed engine check: Ranked first · Bxb5 c6 Ba4 Qh4+.

  8. 4...Qh4+ A forcing check

    Board fact: Black moves the queen from d8 to h4; the move checks White's king; from h4 it attacks White's pawn on h2.

    Fixed engine check: Ranked first · Qh4+ Kf1 g5 d4.

  9. 5.Kf1 Answering the check

    Board fact: White answers the check by moving the king from e1 to f1; from f1 it reinforces the knight on g1.

    Fixed engine check: Ranked first · Kf1 Ne7 Nc3 g5.

  10. 5...g5 Advance the g-pawn

    Board fact: Black moves the pawn from g7 to g5; from there it controls f4.

    Fixed engine check: Ranked first · g5 Nc3 Ne7 d4.

  11. 6.Nc3 Develop the knight

    Board fact: White develops the knight from b1 to c3; from there it controls d5 and e4.

    Fixed engine check: Near the leading choice · Nc3 Bg7 Nf3 Qh5.

  12. 6...Bg7 Develop the bishop

    Board fact: Black develops the bishop from f8 to g7; from g7 it attacks White's knight on c3.

    Fixed engine check: Ranked first · Bg7 d4 Nc6 Nd5.

  13. 7.d4 Claim central space

    Board fact: White moves the pawn from d2 to d4; from there it controls e5 and c5.

    Fixed engine check: Ranked first · d4 Nc6 Nf3 Qh5.

  14. 7...Ne7 Develop the knight

    Board fact: Black develops the knight from g8 to e7; from there it controls d5, c6 and f5.

    Fixed engine check: Ranked first · Ne7 Nf3 Qh6 h4.

  15. 8.Nf3 Develop the knight

    Board fact: White develops the knight from g1 to f3; from f3 it attacks Black's queen on h4 and Black's pawn on g5.

    Fixed engine check: Ranked first · Nf3 Qh5.

  16. 8...Qh5 Create pressure on f3

    Board fact: Black moves the queen from h4 to h5; from h5 it attacks White's knight on f3 and White's pawn on h2.

    Fixed engine check: Ranked first · Qh5 h4 h6 Kg1.

  17. 9.h4 Create pressure on g5

    Board fact: White moves the pawn from h2 to h4; from h4 it attacks Black's pawn on g5.

    Fixed engine check: Ranked first · h4 h6 Kg1 g4.

  18. 9...h6 Advance the h-pawn

    Board fact: Black moves the pawn from h7 to h6; from h6 it reinforces the pawn on g5.

    Fixed engine check: Ranked first · h6 Kg1 g4 Nh2.

  19. 10.e5 Claim central space

    Board fact: White moves the pawn from e4 to e5; from there it controls d6 and f6.

    Fixed engine check: Recorded move; Kg1 ranked higher · e5 Bb7.

  20. 10...Nf5 Create pressure on d4

    Board fact: Black moves the knight from e7 to f5; from f5 it attacks White's pawn on d4 and White's pawn on h4.

    Fixed engine check: Recorded move; Bb7 ranked higher · Nf5 Kg1.

Middlegame · 11.Kg1 to 20.Qh4+

  1. 11.Kg1 Reposition the king

    Board fact: White moves the king from f1 to g1; from g1 it reinforces the rook on h1.

    Fixed engine check: Ranked first · Kg1 Bb7 hxg5 Bxf3.

  2. 11...Ng3 Create pressure on h1

    Board fact: Black moves the knight from f5 to g3; from g3 it attacks White's rook on h1.

    Fixed engine check: Recorded move; Bb7 ranked higher · Ng3 Rh2 Bb7 hxg5.

  3. 12.Rh2 Improve the rook

    Board fact: White moves the rook from h1 to h2; from h2 it reinforces the pawn on g2.

    Fixed engine check: Ranked first · Rh2 Bb7 hxg5 Bxf3.

  4. 12...Qg6 Create pressure on c2

    Board fact: Black moves the queen from h5 to g6; from g6 it attacks White's pawn on c2.

    Fixed engine check: Recorded move; Bb7 ranked higher · Qg6 Bd3.

  5. 13.Nd5 Create pressure on c7

    Board fact: White moves the knight from c3 to d5; from d5 it attacks Black's pawn on c7 and Black's pawn on f4.

    Fixed engine check: Near the leading choice · Nd5 Bb7 Nxc7+ Kd8.

  6. 13...Kd8 Reposition the king

    Board fact: Black moves the king from e8 to d8; from d8 it reinforces the bishop on c8.

    Fixed engine check: Recorded move; Na6 ranked higher · Kd8 hxg5 hxg5 Rxh8+.

  7. 14.hxg5 Exchange on g5

    Board fact: White's pawn takes the pawn on g5; the move changes the central pawn contact; White accepts doubled pawns on the g-file; from g5 it attacks Black's pawn on h6; white is ahead by 1 conventional material point after the capture.

    Fixed engine check: Ranked first · hxg5 Bb7 Bd3 Qe6.

  8. 14...hxg5 Recapture on g5

    Board fact: Black's pawn recaptures the pawn on g5; the move changes the central pawn contact; from g5 it reinforces the pawn on f4; material is level after the capture.

    Fixed engine check: Ranked first · hxg5 Rxh8+ Bxh8 Nxg5.

  9. 15.Rxh8+ Capture with check on h8

    Board fact: White's rook takes the rook on h8; the move checks Black's king; the rook now occupies the open h-file; white is ahead by 5 conventional material points after the capture.

    Fixed engine check: Ranked first · Rxh8+ Bxh8 Nxg5 Bb7.

  10. 15...Bxh8 Recapture on h8

    Board fact: Black's bishop recaptures the rook on h8; from h8 it attacks White's pawn on e5; material is level after the capture.

    Fixed engine check: Ranked first · Bxh8 Nxg5 Nc6 Nxf4.

  11. 16.Nxg5 Exchange on g5

    Board fact: White's knight takes the pawn on g5; from g5 it attacks Black's pawn on f7; white is ahead by 1 conventional material point after the capture.

    Fixed engine check: Ranked first · Nxg5 Nc6 Nxf4 Bxe5.

  12. 16...Qxg5 Recapture on g5

    Board fact: Black's queen recaptures the knight on g5; from g5 it attacks White's pawn on e5; black is ahead by 2 conventional material points after the capture.

    Fixed engine check: Near the leading choice · Qxg5 Bxf4 Qh5 Bxg3.

  13. 17.Bxf4 Exchange on f4

    Board fact: White's bishop takes the pawn on f4; from f4 it attacks Black's queen on g5 and Black's knight on g3; black is ahead by 1 conventional material point after the capture.

    Fixed engine check: Ranked first · Bxf4 Qh5 Bxg3 Qxd1+.

  14. 17...Qh4 Create pressure on f4

    Board fact: Black moves the queen from g5 to h4; from h4 it attacks White's bishop on f4.

    Fixed engine check: Recorded move; Qh5 ranked higher · Qh4 Bxg3 Qg5 Qe1.

  15. 18.Bxg3 Exchange on g3

    Board fact: White's bishop takes the knight on g3; from g3 it attacks Black's queen on h4; white is ahead by 2 conventional material points after the capture.

    Fixed engine check: Ranked first · Bxg3 Qg5 Qe1 Qh6.

  16. 18...Qxg3 Recapture on g3

    Board fact: Black's queen recaptures the bishop on g3; from g3 it attacks White's pawn on e5 and White's pawn on g2; black is ahead by 1 conventional material point after the capture.

    Fixed engine check: Recorded move; Qh7 ranked higher · Qxg3 Qh5 Bg7 Qxf7.

  17. 19.Qh5 Create pressure on h8

    Board fact: White moves the queen from d1 to h5; from h5 it attacks Black's bishop on h8 and Black's pawn on f7.

    Fixed engine check: Ranked first · Qh5 Bg7 Qxf7 Qe3+.

  18. 19...Qg7 Create pressure on e5

    Board fact: Black moves the queen from g3 to g7; from g7 it attacks White's pawn on e5 and White's pawn on g2.

    Fixed engine check: Recorded move; Qe3+ ranked higher · Qg7 Qh4+ f6 exf6.

  19. 20.Qh4+ A forcing check

    Board fact: White moves the queen from h5 to h4; the move checks Black's king; from h4 it attacks Black's bishop on h8.

    Fixed engine check: Ranked first · Qh4+ f6 exf6 Qxf6.

PGN

[Event "London m9"] [Site "?"] [Date "1851.??.??"] [White "Anderssen, Adolf"] [Black "Loewenthal, Johann Jacob"] [Result "1-0"] 1. e4 e5 2. f4 exf4 3. Bc4 b5 4. Bxb5 Qh4+ 5. Kf1 g5 6. Nc3 Bg7 7. d4 Ne7 8. Nf3 Qh5 9. h4 h6 10. e5 Nf5 11. Kg1 Ng3 12. Rh2 Qg6 13. Nd5 Kd8 14. hxg5 hxg5 15. Rxh8+ Bxh8 16. Nxg5 Qxg5 17. Bxf4 Qh4 18. Bxg3 Qxg3 19. Qh5 Qg7 20. Qh4+ 1-0

Sources and checking

Score source: Chess Database, version 1 by Ana Schaigorodsky (2016), licensed under CC BY 4.0. LibreChess selected the exact score identified by sha256:9a63c2200e24e7f9dc5a2362102f37d70c1f4d071052f94fc787b8c583f0a110 and pins it in the selection manifest.
Exact Figshare tags:
White="Anderssen, Adolf"; Black="Loewenthal, Johann Jacob"; Event="London m9"; Date="1851.??.??"; Result="1-0". LibreChess parsed the main line with chess.js and stores normalised SAN. Source comments, side variations and termination detail were not retained.

LibreChess checks every SAN move with chess.js and compares the result and move sequence with a stored reference. The engine comparison was calculated offline from the fixed settings above; it is not a source for historical claims. No termination is inferred where the imported score does not preserve one.

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