阳火虎年 (male Fire-Tiger) 433 or 52 or −720 — to — 阴火兔年 (female Fire-Rabbit) 434 or 53 or −719
Year 307 (CCCVII) was a common year starting on Wednesday of the Julian calendar. At the time, it was known as the Year of the Consulship of Severus and Maximinus (or, less frequently, year 1060 Ab urbe condita). The denomination 307 for this year has been used since the early medieval period, when the Anno Dominicalendar era became the prevalent method in Europe for naming years.
Galerius sends Valerius Severus with the army of northern Italy, to suppress the rebellion in Rome. However, faced with their former emperor Maximian, the soldiers desert him, and Severus flees to Ravenna. Maximian besieges Severus in Ravenna, who then surrenders. Maxentius makes Severus a hostage, in an attempt to keep Galerius at bay.
Summer: Anticipating an offensive by Galerius, Maximian travels to Gaul to make an alliance with Constantine I.
Late summer or autumn: Galerius invades Italy but Maxentius remains behind the walls of Rome. Galerius finds he cannot besiege the city, and the image of an emperor making efforts against Rome hurts Galerius' image among the troops. The fact that Maxentius is his son-in-law does not help, and Maxentius makes an effort to bribe Galerius' troops. Galerius unsuccessfully attempts to negotiate, and recognizing Maxentius' attempts at bribery and the danger of being trapped in Italy by Maximian and Constantine, Galerius chooses to withdraw from Italy. To satiate his troops during the withdrawal, he pillages the Italian countryside. Meanwhile, Maxentius executes Severus.
December: Constantine marries Maximian's daughter Fausta, and is promoted to Augustus by Maximian.[1]
January 8 – Emperor Hui of Jin dies after a 16-year reign, in which eight dukes of the imperial family have conducted a civil war (War of the Eight Princes) against each other in a struggle for power. Huai of Jin, age 23, succeeds his father and becomes the third ruler of the Jin Dynasty.