Larry Mark Christiansen was born in Riverside, California. He is known as a very strong attacking player. He won the National High School Championship in 1971 while still in junior high school, the first ever to do so. He won three invitational U.S. Junior Championships. After winning Torremolinos 1977, he became a Grandmaster at the age of 21, skipping over the usual step of becoming an International Master first.

Christiansen won the U.S. Championship in 1980 (1), 1983 (2) and 2002 (3). He has also won the U.S. Open thrice. He won the 2009 U.S. Senior Championship. He is an eleven-time member of the United States Olympiad team. He was inducted into the U.S. Chess Hall of Fame in 2000.

His international wins include 1st place at Linares in 1979 and in 1981, the latter jointly with Anatoly Karpov Cologne 1988, Wiesbaden 1994, Reykjavik 1998, Essen 1999, and the 2001 Canadian Open. His strong result in the United States Championship (2013) qualified him for the World Cup (2013), where he lost to Frenchman Laurent Fressinet in the first round. He was a frequent competitor at the Bundesliga in Germany.

Larry is also one of the most prolific Internet chess players, having played tens of thousands of games online at the Internet Chess Club under the handle "Larry C." (1)

Christiansen was editor-in-chief of the Players Chess News (1981-84). He has written a number of books, including 54th Hastings International Chess Congress 1978-1979 (1979); Tallinn 1979: VI Paul Keres Memorial Chess Tournament (1979); 1980 U.S. Championship (with Tim Redman) (1980); U.S. Championship 1983 (1983); Dutch Defense (with Jeremy Silman) (1989); On Top of the Chess World: The 1995 World Chess Championship Match (with John Fedorowicz and Ilya Gurevich (1995); Storming the Barricades (2000); and Rocking the Ramparts (2004).

Wikipedia article: Larry Christiansen; (1) http://graeme.50webs.com/chesschamp...; (2) http://graeme.50webs.com/chesschamp...; (3) http://graeme.50webs.com/chesschamp... https://www.uschesschamps.com/bio/l...