Johnathan Dennison was the mayor of Swallow Hills from 2065 to 2077, one of the few liberal minded politicians in active office in the pre-war United States. He maintained a steady grip on power in Swallow Hills throughout his 12 years in office, navigating through deals between Vault Tec for the construction of a Vault and dealing with the presence of the United States Armed Forces in the town. Following the Great War, Johnathan Dennison was chosen as the first Overseer of Vault 42, remaining a staunch liberal even in the face of overwhelming tragedy and outrage.