by Bingley
Shapur or Sapor was the second ruler of the Persian Sassanid empire. Appointed co-ruler with his father Ardashir I in 240 CE, he reigned as sole ruler from 241 to 272. He fought three major campaigns against the Romans, in 242-4, 252-6, and 260. In the last campaign, the Roman emperor Valerian was captured and killed by the Persians.
Using labour and skills from Roman captives, Shapur undertook a massive building programme. He promoted Zoroastrianism, but under his reign the Sassanid state seems to have been religously tolerant, with Christians and Jews having freedom to worship. The prophet Mani, the founder of Manichaeism, was active during Shapur's reign.
Gibbon talks about Shapur (Sapor) in Chapter X.
Wikipedia and CAIS (Circle of Irananian Studies) articles on Shapur both seem to be derived from the 1911 Britannica article. CAIS adds a lot more information from Persian sources, in particular
inscriptions set up by Shapur himself. The Wikipedia article has better
pictures, some of which come from a livius.org list with coin
portraits and
historical overview of
the Sassanids.
Rider: As always, handle Wikipedia with care!