
Jeff 'Swampy' Marsh
Biography
Jeff "Swampy" Marsh (born December 9, 1960) is an American animator, writer, director, producer, and voice actor associated with several animated television series, most notably as an executive producer and the voice of Major Monogram for Disney's animated series Phineas and Ferb and Milo Murphy's Law, both of which he co-created with Dan Povenmire. Marsh was born in Santa Monica, California, where he grew up with a heavily blended family dynamic. Marsh has been and continues to be a driving force behind several animation projects, working for over six seasons on the animated television series The Simpsons. Marsh continued to work on other animated television series, including King of the Hill and Rocko's Modern Life, before moving to England in 1996.
Acting (15 movies)

TV's Funniest Animated Stars: A Paley Center for Media Special
2015

Phineas and Ferb The Movie: Across the 2nd Dimension
2011

O.W.C.A. Files
2015

Phineas and Ferb: Night of the Living Pharmacists
2014

Phineas and Ferb Christmas Vacation!
2009

Phineas and Ferb: The Perry Files - Animal Agents
2013

Phineas and Ferb: The Daze of Summer
2012

Phineas and Ferb: Summer Belongs to You!
2010

Phineas and Ferb: Last Day of Summer
2015

Phineas and Ferb: Mission Marvel
2013

Phineas and Ferb: Star Wars
2014

I Know That Voice
2014

Phineas and Ferb the Movie: Candace Against the Universe
2020

Phineas and Ferb Save Summer
2014

Spiked
2025
| Title | Year | Job |
|---|---|---|
| Phineas and Ferb Christmas Vacation! | 2009 | Producer |
| Phineas and Ferb The Movie: Across the 2nd Dimension | 2011 | Executive Producer |
| Phineas and Ferb The Movie: Across the 2nd Dimension | 2011 | Writer |
| Phineas and Ferb: The Daze of Summer | 2012 | Writer |
| O.W.C.A. Files | 2015 | Executive Producer |
| Phineas and Ferb the Movie: Candace Against the Universe | 2020 | Executive Producer |
| Phineas and Ferb the Movie: Candace Against the Universe | 2020 | Writer |