Sébastien Loeb won nine consecutive WRC drivers' titles. His remarkable championship run lasted from 2004 through 2012, making him one of the most dominant competitors in motorsport history. He drove for Citroën for most of that period, with Kronos Citroën running his car in 2006 while Citroën temporarily stepped away as a constructor.
Loeb's first WRC title came in 2004, after he finished runner-up to Petter Solberg the previous season. He then successfully defended the championship eight times. His ninth and final consecutive title was secured in 2012, after which he stepped away from full-time WRC competition.
The number nine is sometimes confused with Loeb's 80 WRC rally victories, another record associated with his career. It is also worth separating consecutive titles from total titles: Sébastien Ogier later matched Loeb's career total of nine championships, but Loeb's nine-title sequence from 2004 to 2012 remains the key fact in this question. Daniel Elena co-drove with Loeb throughout the historic run.