According to the Jannette R. Trotter Papers in the McClung Historical Collection in Knoxville,Tennessee and the book "Leaves From the Family Tree" by Elizabeth Cate Manley, we can learn the following about the Immigrant Julian ancestor in America...
René is said to have been a giant in stature with red hair, a quick temper and an indomitable will, a Presbyterian of the strictest form who particularly disliked the Quaker Testimony against war and slavery. René, who was born in France in 1669, was a Huguenot who fought at the Battle of Boyne in Ireland in 1690 and came to America about 1700. Family tradition has him stopping at the Island of Bermuda where he married Mary Bullock.
He was a soldier in his youth and was in the army of King James II in the English Revolution of 1688. For reasons of religious preference, he is said to have deserted to the standard of King William (a Protestant) along with many others. For his services to King William, he was given a grant of land on the Mississippi River (another source says the it was in the James River District in what is now Maryland). He went first to the shores of South Carolina, and, losing two sons there, he moved to the more healthy region of the Eastern shore of Chesapeake Bay. (There was a colony of French families on the Santee River in South Carolina who began to migrate away from there around 1712, due to the unhealthy climate. René's family may well have been among them.)
René Julien and his family were living in Cecil County, Maryland, in 1712. The earliest record of René in Bohemia Manor is in 1720 as shown by land leases. The rest of the period from 1712 until 1720 is blank so far as he is concerned, except for the record of the birth of his son, Isaac, in 1716, which appears in the Register of St. Ann's Parish at Annapolis, which is now in the Hall of Records there.
René and Mary had seven sons and three daughters who grew up in Bohemia Manor, Cecil County, Maryland. Whether or not they were born there is uncertain. It is known that two of his daughters were married there, and it is probable that some of the other children were also. By 1737, When René assigned his lease in Bohemia Manor to Henry McCoy, he was 68 years old. It is assumed that this is the date of his leaving for Winchester, Frederick County, Virginia. René was still living in 1744, the last documentary date for him that is known to exist. It is thought that he and his wife are buried among the stones of old Opequon Cemetery near Winchester. The land for this cemetery was given by William Hodge into whose family their son Isaac Julien (aka "Julian") married.
The Julien family (Julian) is one of the most noteworthy of the old American lines. Today over 80% of Julian descendants trace their ancestry to René Julien. Numerous descendants of René Julien fought during the American Revolution, including Isaac Julien who received a Revolutionary War Pension. As our line of the family descended to the fourth generation in America the Julian family made its way to Tennessee. The family homesteaded East Tennessee in the early 1800's. Numerous Julian descendants from East Tennessee fought for the South during the War Between the States (US Civil War: 1861-1865) such as, Lt. John Julian of the 36th Tennessee Infantry, Sgt. Marcena L. Julian also of the 36th and William I. Julian of the 5th Tennessee Cavalry. The Julians became large landowners in McMinn and Bradley Counties in Tennessee and across the state line into northern Georgia. Volumes have been written about the family and extensive histories exist about the Julian families in America, however the following descendants of Count René de Saint Julien directly relate to the East Tennessee line and the descendants of James A. P. Guthrie and Mary Adeline Julian.
He is listed as "St. Julien, René" on the Huguenot Society of America's list of Ancestors. Past and current members have joined the Huguenot Society of America by right of descent from the following Huguenot ancestors who qualify under the constitution of the Society. 
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