John Jenkins was born in about 1754. A resident of Fairfield District, South Carolina, in 1776 he enlisted as a private for eighteen months in the 3rd South Carolina Regiment of the Continental Line. He saw combat at the Siege of Charleston and served at least half of his service term as a sergeant, though unofficially. While on a furlough at home in November 1777, he married Sarah Dye. Their first son Jesse was born the following year. After being discharged from the Continental Line, he reenlisted in the Fairfield District Regiment of the South Carolina Militia in the summer of 1778, leaving his wife to raise their son and tend to the crops. He served one additional three month term in 1781.

By 1800 Sarah and John Jenkins were living with their adult son Jesse and his family. In 1810 they were listed as residing in Chester, South Carolina and by 1820 they were residing in Rutherford County, North Carolina.

In 1827 he applied for a veteran's pension under the Pension Act of 1818, which required applicants to prove their indigent circumstances prior to receiving any compensation. In that application, he stated that he and his wife had been living with their son Jesse in Rutherford County, North Carolina since about 1807 and that he owned no personal property aside from the clothes he was wearing. His claim was successful and he received as pension of $96 a year from October 1827 until his death on July 6, 1830.