Excerpts from Books and Wikipedia
"After consolidating his rule over the western provinces, Severus waged another brief, more successful war in the east against the Parthian Empire, sacking their capital Ctesiphon in 197 and expanding the eastern frontier to the Tigris. . . . The Christian apologist Tertullian stated that Severus was well disposed towards Christians, employed a Christian as his personal physician and had personally intervened to save several high-born Christians known to him from the mob. Eusebius' description of Severus as a persecutor likely derives merely from the fact that numerous persecutions occurred during his reign, including those known in the Roman martyrology as the martyrs of Madaura, Charalambos and Perpetua and Felicity in the Roman province of Africa. These were probably the result of local persecutions rather than empire-wide actions or decrees by Severus." [Wikipedia]