REBEL was a world champion chess program developed by Ed Schröder. Development of REBEL started in 1980 on a TRS-80, and it was ported many times to dedicated hardware and the fastest microprocessors of the day:

• 1980s - Running on a TRS-80, Apple II, and inside of Mephisto brand dedicated chess computers, it won the Dutch open computer chess championship four times.
• 1991 - Ported to the ARM Chessmachine and named Gideon, it won the World Microcomputer Chess Championship.
• 1992 - Gideon won the World Computer Chess Championship, the first time a microprocessor came ahead of a field of mainframes, supercomputers, and custom chess hardware.
• 1990s - REBEL was ported to Microsoft DOS and then Microsoft Windows and sold commercially
  • 1997 - REBEL won a match with GM Arthur Yusupov 10.5 - 6.5, the first successful challenge of a chess grandmaster by a commercial program.
  • 1998 - REBEL won a match with GM Viswanathan Anand 5 - 3 (but lost 0.5-1.5 in the standard time control section of the match). He was rated number two in the world at the time.
• 2004 - Ed Schröder retired, releasing the last version of REBEL as the freeware chess engine Pro Deo.

External links

• Ed's recollection of REBEL's history
• Wealth of information on the inner workings of a professional program
• "How REBEL Plays Chess" by Ed Schröder (PDF)