John Holden Warren

John Holden Warren (August 23, 1825 – August 1, 1901) was an American medical doctor, Republican politician, and Wisconsin pioneer. He served two years in the Wisconsin State Senate representing Green County. In historical documents, his middle name is sometimes spelled "Halden".

Biography John Holden Warren was born in Hogansburg, Franklin County, New York, in August 1825. He attended the common schools in that community until age 13, when he went west to the Wisconsin Territory. He first came to Janesville, Wisconsin, when there were just two families residing there, and he attended the first school taught at that settlement. He went on to study the medical profession under Dr. Samuel Nichols in Janesville. After leaving office, he served as chief clerk of the Senate for the next three terms.

In 1862, he was collector of internal revenue at Albany by President Abraham Lincoln, and held that office for seven years. He owned a carriage service and was a major mail contractor, operating over one hundred mail routes.

Around 1885, he began to suffer from dementia and was sent to the sanitarium at Palmyra, Wisconsin. He died there in August 1901.