Gomoku — the "five in a row" game played with black and white stones on a grid — is one of the oldest abstract strategy games still played today. Its history reaches back thousands of years, crossing continents and picking up new names, rules, and variations along the way.

Origins in Ancient China

The earliest known ancestor of Gomoku is the Chinese game Wuziqi (五子棋), literally "five-piece chess." Chinese tradition traces it to legendary antiquity, but the earliest written references to alignment games on grid boards date from the Spring and Autumn period (770–476 BCE) and later. The game almost certainly shares a common origin with Go: both use the same equipment — a grid board and black and white stones — and were played with pebbles or simple markers long before they were formalized.

Wuziqi was played across Chinese society for centuries. The rules are easy to teach but rich in tactical possibility, so the game served as both a casual pastime and a way to practice pattern recognition and foresight.

Spread to Japan and the Name "Gomoku"

Gomoku traveled to Japan along the same cultural routes as Go and became known there as Gomoku Narabe (五目並べ), "five points in a row." By the Edo period (1603–1868) it was widely played as a lighter alternative to Go, and the earliest Japanese books on the game began to appear in the 19th century.

Japanese players also noticed early on that the first player (Black) had a clear advantage under unrestricted rules. In 1899, the journalist and strong player Kuroiwa Ruikō (黑岩泪香) promoted a standardized name for the professional variant: Renju (連珠, "connected pearls"). Renju added restrictions on Black — including bans on double threes, double fours, and overlines — to create a more balanced contest. Today Renju is governed by the International Renju Federation and has its own world championship.

Korea, Vietnam, and the Wider World

The game was also popular in Korea, where it is called Omok (오목), and in Vietnam, where it is known as Caro (Cờ ca-rô). In Korea, Omok became a well-known café and schoolyard game, with its own televised tournaments and professional associations. Korean players have contributed heavily to modern opening theory and to the study of the game by computer programs.

Arrival in the West

Gomoku reached Europe and North America in the late 19th and early 20th centuries, often through Japanese cultural exchange. It became a staple of school clubs and recreational play, and was marketed in boxed sets as "Five in a Row" or "Gomoku." In the 20th century, the game also became a standard test case in computer science departments, where its simple rules and deep strategy made it ideal for experiments in game-tree search and artificial intelligence.

The Computer Age

In 1994, Dutch computer scientist Victor Allis proved in his doctoral thesis that freestyle Gomoku on a 15×15 board is a first-player win: with perfect play, Black can always force a victory. His program, Victoria, used threat-space search and proof-number search to solve the game. This result confirmed what many players already suspected and reinforced the need for balanced rule sets like Renju and swap-based opening protocols in serious competition.

Modern Gomoku engines such as Yixin and Embryo play far above human level under freestyle rules and have built enormous databases of opening patterns. Studying engine analysis is now a normal part of training for competitive players.

Gomoku Today

Today, Gomoku is played in three main forms:

  • Standard Gomoku — free placement, no restrictions, popular for casual play.
  • Renju — the professional variant with restrictions on Black's first moves and certain forbidden shapes.
  • Freestyle Gomoku — competitive but unrestricted; the standard format for many international online tournaments.

Online Gomoku is especially popular in China, Korea, Japan, Russia, and Eastern Europe, with platforms hosting thousands of concurrent games. The game also thrives on mobile apps, in classrooms, and in family kitchens around the world.

Why Gomoku Endures

Gomoku survives because it combines extreme accessibility with real depth. A child can learn the rules in a minute, while a serious player can study it for years. It needs almost no equipment: a grid, two colors of stones, and two players. In that simplicity is the reason it has been played, in one form or another, for millennia.

Ready to play? Play Gomoku online for free or read the rules of the game.