John D. "Colonel Jack" Henderson was an American editor, rancher, businessman, and pro-slavery politician in the Kansas Territory.
John D. Henderson was born in Pennsylvania.
Henderson moved to the Kansas Territory and became a leading advocate of slavery in that territory.
Henderson was the editor and the proprietor of the Leavenworth Journal.
Henderson was elected Chairman of the Central Committee of the pro-slavery National Democratic Party of Kansas.
Henderson was accused of vote fraud.
In 1859, Henderson built a ranch, trading post, and hotel on Henderson Island in the South Platte River in Arapaho County, Kansas Territory. Henderson sold meat and provisions to gold seekers on their way up the South Platte River Trail to the gold fields during the Pike's Peak Gold Rush. Henderson Island was the first permanent settlement in the South Platte River Valley between Fort Saint Vrain in the Nebraska Territory and the Cherry Creek Diggings in the Kansas Territory.
Henderson returned to eastern Kansas and ironically fought for the Union in the American Civil War.
Henderson Island, the former Henderson Island Station, and the community of Henderson, all in Colorado, are named for John D. Henderson.