One belief is that when Galerius himself invaded Italy to suppress Maxentius and Maximian, the former ordered Severus's death, and that he was executed (or forced to commit suicide) on September 307 at Tres Tabernae, near the current Cisterna di Latina.
Satu kepercayaan menyatakan bahwa Galerius sendiri menginvasi Italia untuk mengejutkan Maxentius dan Maximian, dan ia dieksekusi (atau dipaksa melakukan bunuh diri) pada 16 September 307 di Tres Tabernae, saat ini dekat Cisterna di Latina.