1680s, "large box of wood, slats, etc., used for packing and transporting," earlier "hurdle, grillwork" (late 14c.), from Latin cratis "wickerwork, lattice, kitchen-rack," or from Dutch krat "basket;" both perhaps from a common PIE root *kert- "to turn, entwine" (see hurdle (n.)).
Used as temporary fencing in agriculture. Sense of "barrier to jump in a race" is by 1822 (hurdle-race also is from 1822); hurdles as a type of race (originally horse race) with hurdles as obstacles is attested by 1836. Figurative sense of "obstacle" is 1924.