[1][2][3] Born in then-vast Augusta County, to Esther Alexander and her schoolmaster husband Robert, who had immigrated from Ulster to the Pennsylvania colony in 1737, then nine years later moved his young family south to the Shenandoah Valley of Virginia, where he established a school that became a predecessor of what became in this man's lifetime Washington College, and is now Washington and Lee University.
[2] Having learned to read and write under his father's tutelage, Alexander on January 25, 1773, became deputy to the clerk of the court of Bedford County (which had been formed in 1753 and would be subject to several boundary changes before 1786).
[4][2] In March 1788, Campbell county voters elected Alexander and lawyer Edmund Winston to represent them at the Virginia Ratifying Convention.
[2] In the 1787 Virginia tax census, he (or possibly a relative with the same name) was identified as both non-tithable and non-resident in Bedford County, but as owning three enslaved teenagers, two adult slaves, three horses and seventeen cattle there.
According to historian Brent Tarter, several colorful anecdotes about early Campbell County featured Alexander, who often carried a large musket and was prone to wild behavior when drunk.