My great great grandfather was William W. Forgus b.1822 Tn.,d1883 Bell County Tx. We have been unable to trace his roots before Monroe Co TN. After reading your message I am wondering if perhaps I should be looking for Fargus rather than Forgus. This may be why I cannot get beyond this point.
He had a son James Marion. I understand it was quite common for the Irish to name the first born after the grandfather and the 2nd son, after the father.