The king of Aram was likely Ben-hadad II who ruled from 860 to 843 BC.
the LORD had given victory to Aram: The Lord rules over all nations (Psalms 47:8; 99:1–2; Romans 13:1).
a leper: Naaman’s ability to be part of society and Gehazi’s later social freedom (2 Kings 8:4–5) suggest the issue was not Hansen’s disease but another serious skin condition (see Leviticus 13:10–11, 45–46).