The mystery surrounding Sterling Archer’s father in Archer was a major question mark for much of the series. While Archer was largely focused on the adventures of Archer and the rest of his co-workers at an independent spy agency, his origins factored into several episodes across the course of the long-running series. This included the truth of his parentage, something his mother Mallory repeatedly refused to divulge despite Sterling’s repeated attempts to discover the truth.

https://screenrant.com/archer-father-biggest-mystery-explained/