The feng sacrifice to Heaven, performed at the summit of Mount Tai in Shandong, and the shan sacrifice to Earth, performed at its foot or at a nearby secondary peak, together formed the most exceptional and rarely attempted ceremony available to a Chinese emperor, and their rarity was itself the entire point: only a ruler who believed his reign had achieved a peace and prosperity so complete that it merited announcement to Heaven and Earth themselves could properly perform the rites, and an emperor who performed feng and shan without that achievement risked being judged by history, and by Confucian scholars in particular, as arrogant or illegitimate rather than as rightfully triumphant.
Mount Tai held a sacred status in Chinese religion considerably older than the imperial ritual itself, regarded as the foremost of the Five Great Mountains and associated with beginnings, sunrise and the transmission of the Mandate of Heaven, which is precisely why the mountain, rather than the capital or any temple, was chosen as the site where an emperor could most convincingly claim to speak directly to the cosmic powers that had granted him rule. Traditional accounts trace performances or claimed performances of the rite back to the semi legendary sage kings, but the historically well attested imperial performances begin with Qin Shi Huang, China's first unifying emperor, in the late third century BCE.