Embleton began as a comic strip artist, and worked on TV Century 21 in the 1960s. He later began working in children's educational illustrations and then advertising. He also paints landscapes and was the first artist to work on the new Dan Dare in 1982.
He is now best known as an illustrator of military and historic subjects. He has illustrated more than 40 titles for the military publisher Osprey.
In 1998, he founded a company called Time-Machine that works with museums all over the world, specializing in vivid displays with 3D figurines.
Gerry Embleton is a founding member of the Company of Saynt George, a living-history association. His book "The Medieval Soldier", co-authored with Tolkien illustrator John Howe, had a big influence on the living-history hobby as a whole.