The dark drama series, starring Claire Danes and Damian Lewis, concluded with 1.7 million viewers in its 10pm timeslot, growing to over 2m across the night's other airings.
As well as being its highest-rated episode since premiering in the fall, Homeland has become Showtime's best freshman series.
Exec producers Alex Gansa and Howard Gordon have said that the show will change radically in next year's second season, which was commissioned in October.
Homeland's first season will premiere in the UK in the New Year on Channel 4.
Watch a trailer for Homeland below: