Bangkok authorities are treating the death as a suicide. Mr. Carradine was the eldest son of stage and film character actor John Carradine, a flamboyant performer known for declaiming Shakespeare while walking down the street. His brother, Bruce; his half-brothers Keith and Robert; and his nieces Ever Carradine and Martha Plimpton all became actors.
As the star of "Kung Fu," the tall, lanky actor was at the center of Kung Fu craze that gripped the United States in the early 1970s. The series, which ran from 1972 to 1975, told of Kwai Chang Caine, a Shoalin Monk who flees to America after he kills the Chinese Emperor's nephew after seeing the man murder his teacher in cold blood. Of course, he finds plenty of trouble in the Wild West as well, and in every episode the peaceful monk is forced to deploy his fighting arts. Meanwhile, he must elude the bounty hunters who are on his trail. The show won him Emmy Award and Golden Globe Award nominations.
Mr. Carradine was never able to escape the strong impression he made in "Kung Fu," which became a frequent subject of parody over the years. Many of subsequent parts were martial-arts-oriented, including his big comeback role as a deadly criminal in "Kill Bill," Tarantino's lengthy homage to the kung-fu-film genre. He was nominated for a Golden Globe Award for the part. From 1992 to 1995, he starred in, and produced, "Kung Fu: The Legend Continues," taking up his old role. He rarely stopped acting, but few of the film and television roles following his initial success in the 1970s were very rewarding.
Carradine was also known for producing and starring in several exercise videos teaching the martial arts of Tai chi and Qi Gong, even though he had no knowledge of martial arts prior to starring in "Kung Fu."
He first found work on Broadway in 1964 in The Deputy. The following year, he played Atahuallpa in Peter Shaffer's The Royal Hunt of the Sun opposite Christopher Plummer. With that experience he returned to Hollywood, landing the short-lived TV series "Shane." In 1972, he starred opposite Barbara Hershey in Martin Scorsese's first Hollywood film, "Boxcar Bertha." He born John Arthur Carradine on Dec. 8, 1936. He changed his name to David when he began acting. He was married five times. He is survived by his wife, Annie Bierman; his son Free, whom he had with actress Barbara Hershey; five daughters, Kansas, Calista, Amanda, Madeline and Olivia; and another son, Max.