THE HAGUE, Netherlands—Maharishi Mahesh Yogi, a yogic guru ( guru to the Beatles), who introduced the Western world to transcendental meditation, died Tuesday at his home in the Dutch town of Vlodrop, a spokesman said. He was thought to be 91 years old. “He died peacefully at about 7 p.m.,” said Bob Roth, a spokesman for the Transcendental Meditation movement that the Maharishi founded. He said his death appeared to be due to “natural causes, his age.”