Gregory Gallant (born September 16, 1962), better known by his pen name Seth, is a Canadian cartoonist. He was born in Clinton, Ontario, Canada, the youngest of five children. His family moved frequently, but he grew up mostly in Tilbury, Ontario.

Seth attended the Ontario College of Art in Toronto from 1980 to 1983. While there he became involved with the punk subculture and began wearing outlandish clothing, bleaching his hair, wearing makeup, and frequenting nightclubs, it was during this time he took on the pen name Seth in 1982. After graduating he continued to reside in Toronto.

In 1985 he was brought on as the series artist for Dean Motter’s Mister X, published by Toronto-based Vortex Comics. His run covered issues #6–13 (1985–88), after which he did commercial artwork for publications including Saturday Night and Fashion. In 1986 he met fellow Toronto-based Vortex artist Chester Brown, and in 1991 Toronto-based American cartoonist Joe Matt. The three became noted for doing confessional autobiographical comics in the early 1990s, and for depicting each other in their works, and they became known as “The Toronto Three”.

In April 1991 he launched his own comic book, Palookaville, with Montreal publisher Drawn & Quarterly. Seth’s artwork had evolved to a strong, nostalgic style, with thick bold lines. Palookaville is still published by D+Q on an semi-annual basis.

He has been a strong pioneer of the graphic novel format with It’s A Good Life, If You Don’t Weaken (1996) (serialized in Palookaville 4-9), Clyde Fans: Part One (2000) (serialized in Palookaville 10-12), Clyde Fans: Part Two (2003) (serialized in Palookaville 13-15), Wimbledon Green (2005), George Sprott (2009) (serialized in the New York Times Magazine in 2006), The Great Northern Brotherhood of Canadian Cartoonists (2011) . Between 2012 and 2015 he collaborated on a series of four books with author Lemony Snicket under the banner All the Wrong Questions –  Who Could That Be at This Hour?, When Did You See Her Last?,  Shouldn’t You Be In School? and Why is This Night Different From All Other Nights? In 2019 Drawn and Quarterly published the complete Clyde Fans, which was nominated for the prestigious Giller Prize.

An art book, Vernacular Drawings, was published in 2001.

He is also a magazine illustrator and book designer, perhaps best known for his work designing the complete collection of Charles M. Schulz’s classic comic strip Peanuts, released by Fantagraphics Books in over two dozen volumes. Similarly, he assembled the Collected Doug Wright, and the John Stanley Library, and most recently, John Stanley’s Nancy for D+Q.

Seth’s artwork has landed on the cover of The New Yorker three times, and he has illustrated covers for prose novels as well as record albums and covers for the prestigious Criterion Collection.

Seth’s highly detailed building models for the fictional Canadian town of Dominion have been on display in numerous art galleries across North America. In 2008, Seth collaborated with the Kitchener-Waterloo Art Gallery and RENDER (now the University of Waterloo Art Gallery), on an exhibition titled “The North Star Talking Picture House”. For this exhibition one of the buildings from Seth’s Dominion City project was re-built at the Kitchener-Waterloo Art Gallery as a walk-in theatre wherein visitors could sit and watch a program of black and white documentary shorts that had been produced by the National Film Board of Canada.

Seth is the subject of the 2014 documentary film Seth’s Dominion, which received the grand prize for best animated feature at the Ottawa International Animation Film Festival.

He is the co-founder of the Doug Wright Awards for Canadian Cartooning, established in 2004 and has designed the trophies for the annual award, handed out in conjunction with the Toronto Comic Arts Festival.