Michelin tires have been a staple on Citroën models since 1919. And when Citroën filed for bankruptcy in 1934, impacted by the depression and cost of developing and getting the Traction Avant to market, Michelin was its largest creditor stepping in to take over the company installing Pierre Michelin as chairman of Citroën early in 1935.
Since Michelin owned Citroën when the X radial was created, models like the 2CV and the Traction Avant (post war) were the first to be equipped with them.
In celebration of the Michelin X Radial tire’s 70th anniversary, the company published an informative article on their website about the X Radial’s history, innovation and applications. Check it out here: https://www.michelin.com/en/news/the-x-radial-tire-is-70-years-old/