The Sasanian (/səˈsɑːniən, səˈseɪniən/) or Sassanid Empire, officially known as the Empire of Iranians (Middle Persian: 𐭠𐭩𐭥𐭠𐭭𐭱𐭲𐭥𐭩, Ērānšahr) and also referred to by historians as the Neo-Persian Empire, was the last Iranian empire before the early Muslim conquests of the 7th-8th centuries AD. Named after the House of Sasan, it endured for over four centuries, from 224 to 651 AD, making it the longest-lived Persian imperial dynasty. The Sasanian Empire succeeded the Parthian Empire, and re-established the Persians as a major power in late antiquity alongside its neighbouring arch-rival, the Roman Empire (after 395 the Byzantine Empire).