Residence in Rockbridge County, Virginia should be verified. It appears there was also a Scots-Irish Cowan family there at that time.
(1)"Morea Abrahams, Theft > receiving, 11th December 1765," The Proceedings of the Old Bailey: London's Central Criminal Court, 1674 to 1913, accessed 3 September 2008.
(2)"Edward Williams, Thomas Peak, Israel Cowen, Theft > burglary, Theft > receiving, Theft > burglary, 3rd June 1767," The Proceedings of the Old Bailey: London's Central Criminal Court, 1674 to 1913, accessed 3 September 2008.
(3)"Edward Williams, Thomas Peak, Israel Cowen, Theft > burglary, Theft > receiving, Theft > burglary, 3rd June 1767," The Proceedings of the Old Bailey: London's Central Criminal Court, 1674 to 1913, accessed 3 September 2008.
(4) Israel Cowan, 1 tithe, Rockbridge County, Virginia, 1782, in Augusta B. Fothergill and John Mark Naugle, Virginia Tax Payers 1782-87 Other Than Those Published by the United States Census Bureau (Baltimore: Genealogical Publishing Co., Inc., 1978), 29.