Originally Posted by MrMacSon

How reliable or true is the information about these characters: Irenaeus, Polycarp, Ignatius, Justin Martyr, etc.

Could the information about them be subject to later redaction and embellishment?

For example, Polycarp's most significant work is said to be his 'letter to the Phillipians', & the most significant work about him is the 'Martyrdom of Polycarp'. There is little to verify these works or Polycarp's roles.