The pilot of the tailwheel equipped airplane reported a left crosswind during approach to the runway. During touchdown the airplane veered to the left of the runway centerline. The pilot attempted to return the airplane to the runway centerline by applying right rudder control and right brake. The airplane veered right and exited the right side of the runway. Approaching a ditch on the right side of the runway, the pilot applied the brakes and the airplane nosed over and came to rest inverted. The pilot exited the airplane and reported seeing a shift in the windsock on the airfield from a left crosswind to a left quartering tailwind. The airplane sustained substantial damage to the left wing strut. The pilot reported no preimpact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation.