Born in the Halton area of Leeds, Sunter began working for the Midland Railway in 1864, as a cleaner.

He was steadily promoted until he became an express train driver, a job he undertook for sixteen years.

[1] Sunter was one of the first members of the Associated Society of Locomotive Engineers and Firemen (ASLEF), which was initially based in Leeds.

He served on the union's first executive committee, which was led by Joseph Brooke, its part-time secretary.

However, he died suddenly, aged 54, on 21 September and was buried at Beeston Hill Cemetery, Leeds, three days later.