What's your evidence that Allen U. Alexander came from Maryland? The Mecklenburg Alexanders; eg Abraham Alexander Sr and kin, originally came from Cecil County, Maryland.
(I am a descendants of Abraham Alexander Jr.)
I thought that it was not know whether Allen U. was a member of this family, or whether he came from a separate Alexander family. If you've got evidence showing that Allen U. came from Maryland that would be very helpful in attaching him to this family.
I didn't see his name in the The Rock Church - A Brief History, but the only Alexanders mentioned by name were Amos and his brother Theophilus, and Theo's son. There were quite a few Alexanders in the area; they resided principally in the New Munster Tract, which is roughly the same area as the Fair Hill Natural Resource Area today. They were elders in The Rock Church, which is now in Cecil County, MD, but was previously in Lewis, PA.
I am researching Mary McClatchey who m. David Alexander, blacksmith, the son of Allen U. Alexander of Elk Shoals Creek. If you have any information on David I'd like to hear it.
I'm also looking for information on Amanda Adelaide Alexander, who was probably the dau. of Allen Alexander, son of Allen U. Alexander. She m. Hamilton Lorenzo Dowell Alexander, he was the son of Mary and David.
The New Sterling ARP Church was indeed named after Sterling Scotland. I am not precisely clear on the founders of this church, but I am under the impression they arrived in the late 1700s, and came via South Carolina. If that's correct, and Allen U. came with these immigrants, then he is unlikely to be related to the Alexanders of Cecil County, Maryland.
The Alexanders of Cecil Co, MD, are Scotch-Irish, descendants of 7 brothers and 2 sisters that came over on the ship Welcome in 1670. The landed on the Eastern Shore, and some later moved to the New Munster Tract, Cecil County, Maryland.