Cowboy Up! Tue, 07/03/2018 - 11:00pm Cowboy Up! The 44th Annual Muscogee (Creek) Nation Festival took place June 22-23, 2018, at the Claude Cox Omniplex in Okmulgee.PLEASE LOG IN FOR PREMIUM CONTENT. Our website requires visitors to log in to view the best local news. Not yet a subscriber? Subscribe today! Read more about Cowboy Up!