| Birth Date: | 3 July 1821 |
| Birth Place: | Bedford County, Virginia, U.S. |
| Death Place: | Laredo, Texas, U.S. |
| Party: | Republican |
| Term Start: | 1867 |
| Term End: | 1875 |
| State House2: | Texas |
| District2: | 67th |
| Termstart2: | November 2, 1857 |
| Termend2: | February 21, 1861 |
| Office: | Chair of the Texas Republican Party |
| Successor: | Edmund J. Davis |
| Predecessor: | Inaugural |
| Successor2: | E.D. Lane |
| Predecessor2: | Anthony Banning Norton |
| Spouse: | Angelica Irene Wells |
| Children: | 5 |
| Battles: | Mexican-American War American Civil War |
| Unit: | 1st Texas Cavalry Regiment |
| Allegiance: | United States (Union) |
| Branch: | U.S. Army (Union Army) |
John Leal Haynes (July 3, 1821 – April 2, 1888) was an American soldier and politician. Haynes was a Southern Unionist and served in the Union Army under Edmund J. Davis during the American Civil War.
Haynes was born on July 3, 1821, in Bedford County, Virginia.[1] He moved to Mississippi in the early 1840s, where he was editor of the Lexington, Mississippi, Advertiser. He volunteered for service during the Mexican-American War rising to the rank of lieutenant. He served in the Texas House of Representatives from 1857 to 1861 representing Rio Grande City in Starr County.[2]
During the Civil War, Haynes served as an officer in Edmund J. Davis's 1st Texas Cavalry and was promoted to colonel of the 2nd Texas Cavalry in 1863. Haynes commanded the consolidated regiment which was reorganized from both the 1st and 2nd Cavalry regiments in 1864.
Following the Civil War, he lived in Austin from 1865 to 1868 where he worked as an internal revenue collector. He ran unsuccessfully for Congress in 1869. Haynes served as a collector of customs in Galveston from 1869 to 1870 and in Brownsville from 1872 to 1884. Haynes was instrumental in developing the Texas Republican Party during Reconstruction, leading the conservative faction of the party in the late 1860s and supporting the regular party in the 1870s. He ran for lieutenant governor in the 1884 Texas gubernatorial election.
Haynes was married to Angelica Irene Wells and had five children. He was a member of the Grand Army of the Republic and Freemason. He died in Laredo on April 2, 1888.