The New Rules

The History of Chess

Course 13 · Chapter 4 · The New Rules

For some seven centuries the game changed slowly. Then, in the later fifteenth century, in southern Europe, its rules were changed in a few decades so that the queen and bishop became the long-range pieces of today and play became much faster. This chapter describes the change, the texts that record it and the debate about its dating. The outline was checked by web search; individual claims are flagged "check".

Before and After

Piece or rule	Old (shatranj style)	New (from the late fifteenth century)
Queen	One square diagonally	Any distance in any straight or diagonal line
Bishop	Two squares diagonally, leaping	Any distance diagonally, without leaping
Pawn's first move	One square	One or two squares; capture "in passing" (en passant) follows
Castling	Various local king moves	King and rook move together, with fixed rules
Promotion	Pawn becomes the weak counsellor	Pawn may become a queen, later also another piece
Pace	Slow, strategic	Fast, tactical, attacking

All entries are the usual summary and individual details varied by region and period (check).

The biggest change in the history of the game Giving the queen the power of rook and bishop together changed the character of chess more than any other single rule. Attacks and mating threats came quickly, and openings became sharper. Surveys describe this as the point at which modern chess begins (check).

Where and When

Valencia

The early texts that show the new moves come from the Kingdom of Valencia, in eastern Spain, in the 1470s to 1490s. A poem on chess and love, Scachs d'amor, written about 1475 in Catalan, is the early text most often cited (check).

The printed book

Francesc Vicent's Llibre dels jochs partitis dels schachs was printed in Valencia in 1495, and is often described as the earliest printed chess book. No copy is known to survive (check).

Spreading

A Spanish book by Luis Ramirez de Lucena, printed about 1497, and an Italian work by Damiano in 1512 helped carry the new game across Europe (check).

Why the Queen?

Why did the weakest piece become the strongest? The answer is not known. Proposals include:

A courtly world. Queens and queenly figures carried great prestige in late medieval courts, and the piece named for a queen may have gained in power with her status (check).
The pawn's promotion. If a pawn which reaches the far side becomes a counsellor, a strong promoted piece is a stronger incentive. Some scholars see promotion and the queen's power as parts of one change (check).
A wish for speed. Players tired of long, slow games, and the new rules rewarded attack.

The first and the third are guesses. No text explains the decision, and a historian should state that plainly.

A pattern to watch The change did not happen on one day in one place. The new moves were first recorded in a handful of texts, and for a time old and new rules existed side by side, with the new game called "chess of the queen" or "mad queen chess" in some later descriptions (check). Wherever an account says "the rules were changed in a year", look for the text.

Reading a Position

One way to feel the difference is to count the squares a lone piece controls. The script below counts the moves of a rook-and-bishop queen on an empty board, against the old one-step counsellor.

# Squares reached from (row, col) on an empty 8x8 board
def old_queen(r, c):
    steps = [(-1, -1), (-1, 1), (1, -1), (1, 1)]
    return [(r + a, c + b) for a, b in steps
            if 0 <= r + a < 8 and 0 <= c + b < 8]

def new_queen(r, c):
    dirs = [(a, b) for a in (-1, 0, 1)
            for b in (-1, 0, 1) if (a, b) != (0, 0)]
    out = []
    for a, b in dirs:
        i, j = r + a, c + b
        while 0 <= i < 8 and 0 <= j < 8:
            out.append((i, j))
            i, j = i + a, j + b
    return out

print(len(old_queen(3, 3)), len(new_queen(3, 3)))   # 4 and 27

Evidence, Weighed

Claim (check each)	Evidence	Verdict
The new rules arose in Spain	Valencian texts of the 1470s and 1490s	The best-supported view, though the dating is debated
Scachs d'amor is the first record of the new queen	A poem, so a literary rather than a technical source	Important, but dating and reading are disputed
Isabella of Castile caused the change	A popular story linking the strong queen to the queen of Spain	No firm evidence; a legend
All Europe changed at once	Spanish and Italian works; slow adoption elsewhere	False; adoption took decades

A British comparison Britain took the new game in the sixteenth and seventeenth centuries, not at once. In Scotland and England the queen had reached full power by the time of the first English printed chess books (check), and in Edinburgh a Lewis queen of the old game can be seen beside the later idea of the strong queen in the National Museum of Scotland's displays of chess and games, if they are on view (check).

Not Yet Verified A web search agreed on the main outline: the new queen and bishop rules are recorded in Valencia in the later fifteenth century, in the poem Scachs d'amor of about 1475, in Vicent's book of 1495, and spread by Lucena and Damiano, with historians still arguing about the exact dating. The search found no source for the term "mad queen" or for the story about Isabella of Castile as a cause. The table of rule changes, the reasons suggested, and the British note come from general knowledge and have not been checked against primary sources; treat every "(check)" accordingly.

Exercises

Exercise 1

List three rule changes of the later fifteenth century and say how each changed the character of the game.

→ Solution

Exercise 2

Explain why the story that Isabella of Castile caused the strong queen should be treated as a legend, and say what evidence would change your mind.

→ Solution

Exercise 3

Run the move-counting script for the corner square (0, 0) and the centre (3, 3), and explain the difference in the results.

→ Solution

Quick Reference

Where: Valencia, 1470s to 1490s; then Spain, Italy, Europe
Texts: Scachs d'amor, Vicent (1495), Lucena, Damiano
Changes: strong queen, long-range bishop, two-square pawn, castling
Method: separate what the texts say from why we think it happened