By February 1646, he was practicing law in York County, Virginia, and also resided at various times in James City and Gloucester Counties.  He was elected as a burgess from James City County in 1655/56 and again in 1663.  He was the sergeant-at-arms for the General Assembly and was appointed to a committee to examine the election of burgesses newly returned to the Assembly.  He was also the High Sheriff of James City County and was listed among the justices of the Gloucester County Court in 1656. He was appointed in 1660 to a committee of the Council and Assembly to make plans to build a state house.

He held the rank of Captain, Major, Lt. Colonel, and Colonel in the militia, though not necessarily in the correct rank sequence.  In the spring of 1664, he was ordered to accompany Edmund Scarborough, the Surveyor General of Virginia, to Manakin to confer with the commissioners about the boundary dispute with Maryland.  

By the mid 1660’s, Ellyson owned land in James City County on Ware Creek and patented land in New Kent County on the narrows of the York River in 1657.  At the same time, he patented 200 acres in James City County on the east branch of Burchen Swamp; his son later re-patented these tracts of land.

The name of Robert Ellyson’s wife cannot be proved, but most printed accounts claim that she was probably Elizabeth Gerrard, the daughter of Dr. Thomas Gerrard.  The Gerrard name was used for several generations of Robert Ellyson’s descendants.  Elizabeth Ellyson was present as a sponsor in 1658 at the baptism of William Randolph, son of Henry Randolph, in James City.  The marriage of Robert and Elizabeth Ellyson probably occurred in the mid-1650’s.

Robert Ellyson had two known children: (1) Gerrard Robert Ellyson, born about 1658; and (2) Hannah Ellyson, wife of Anthony Armistead, born by or before 1660.  When Gerrard Robert Ellyson recorded the patent his father had made in 1657 for 577 acres in New Kent County, he identified himself as “sonne and Heire” of Robert Ellyson. In July, 1698, Hannah Armistead deeded land that was given by her father, Robert Ellyson, to her son-in-law, John West.

Gerrard Robert Ellyson, orphan of Major Ellyson, was under age in Oct 1672, when the James City County court ordered that Mr. Thomas Viccars be his guardian.  Whether Hannah was older is not certain, but she had a son-in-law by 1698.

Dr. Robert Ellyson continued to practice medicine his entire life and died 28 Sep 1681 in James City County, Virginia.
 
First Mississippi Company Descendants of Dr. Robert Ellyson: Rev. Janin Ryniker Goff, Dr. Michael Lee Davis