That "Possible" is a big word isn't it. It seems the farther back you go the more it shows up. My search isn't so much ancient history. My father was a Grandson of Thomas Clarkson. Dad's Mother was Harriett Clarkson. We must assume that the same last names indicates he was born out of wed lock. A real stigma for a kid growing up arround the turn of the century. He made the military his career, rose through the ranks to become an officer. After retirement he was elected President of the School Board and was the Worshipful Master of the Masonic Lodge. For obvious reasons he told us very little about his childhood. I am now trying to find out who his Father really was.
An interesting tale was told to me by Gwen Clarkston Shea. She is now the Secretary of State for the State of Texas and goes by Gwen Shea. According to her the Clarksons and the Clarkstons (her ex-husbands family) were all Clarksons when they came to America. At some point one of the family members was hung as a horse thief. The rest of the Clarksons stuck the "T" in his branch of the family name to seperate them and to indicate they were the thiefs. I'm sure most of that is Texas Tall Tale and the rest is ex-wife talk but it's as good an explaination as I have heard.
Good luck in your search. Let me know if you come accross anything that might be of interest to a Clarkson. Regards, Joe Clarkson Irving TX