John Allen Campbell (October 8, 1835 – July 14, 1880) was a politician and officer in the United States Army, as well as the first Governor of the Wyoming Territory.

On February 24, 1866, President Andrew Johnson nominated Campbell for appointment to the grade of brevet brigadier general of volunteers, to rank from March 13, 1865, and the United States Senate confirmed the appointment on April 10, 1866.

Both John and Isabella are buried at the Arlington National Cemetery, Washington, D.C.[6] Campbell continued to serve under Major General Schofield during the Reconstruction Period, and in Virginia Campbell helped set up senatorial and representative districts.

While Governor, Campbell approved the first law in United States history explicitly granting women the right to vote.

[8] Campbell was appointed American Consul at Basel, Switzerland, on December 3, 1877, and resigned on February 4, 1880.