Constantine VII Porphyrogenitus (Greek: , translit. Knstantinos Porphyrogenntos; 17 May 905 9 November 959) was the fourth Emperor of the Macedonian dynasty of the Byzantine Empire, reigning from 6 June 913 to 9 November 959. He was the son of Emperor Leo VI and his fourth wife, Zoe Karbonopsina, and the nephew of his predecessor Emperor Alexander.

Most of his reign was dominated by co-regents: from 913 until 919 he was under the regency of his mother, while from 920 until 945 he shared the throne with Romanos Lekapenos, whose daughter Helena he married, and his sons. Constantine VII is best known for the Geoponika ( ), an important agronomic treatise compiled during his reign, and his four books, De Administrando Imperio (bearing in Greek the heading ), De Ceremoniis ( ), De Thematibus ( ), and Vita Basilii ( ).The epithet porphyrogenitus alludes to the Purple chamber of the imperial palace, decorated with porphyry, where legitimate children of reigning emperors were normally born. Constantine was also born in this room, although his mother Zoe had not been married to Leo at that time. Nevertheless, the epithet allowed him to underline his position as the legitimate son, as opposed to all others, who claimed the throne during his lifetime. Sons born to a reigning Emperor held precedence in the Eastern Roman line of succession over elder sons not born "in the purple".

Stephen Lekapenos or Lecapenus (Greek: Στέφανος Λεκαπηνός, Stéphanos Lekapenós; died 18 April 963) was the second son of the Byzantine emperor Romanos I Lekapenos (r. 920–944), and co-emperor from 924 to 945. With his younger brother Constantine, he deposed Romanos I in December 944, but was overthrown and exiled by the legitimate emperor Constantine VII (r. 913–959) a few weeks later. Stephen lived out his life in exile on the island of Lesbos, where he died on Easter 963.