The mantra was popularized by Chaitanya Mahaprabhu roughly around 1500 C.E. when he began his mission to spread this mantra publicly to "every town and village" in the world, travelling throughout India, and especially within the areas of Bengal and Odisha. Some versions of the Kali Santarana Upanishad give the mantra with "Hare Rama" preceding "Hare Krishna" (as quoted above), and others with "Hare Krishna" preceding "Hare Rama", as in Navadvipa version of the manuscript. The latter format is by far the more common within the Vaishnava traditions. It is a common belief that the mantra is equally potent when spoken in either order.