I have a little information on the family. Send me an e-mail if you want. I can trace it non-conclusively back to France. Also some interesting links to Scotland. Family is different from that in South Carolina.
My Great-grandfather was Frank Issac LaRoche
who lived in Savannah during the War between the States. His father was either the brother or nephew of Issac Drayton LaRoche -- I do not have my records in front of me.
In any event the Family was a merchant family for many years in Savannah and the Augusta Area. The first LaRoche in the new world was related to two of the signers of the Georgia Charter (1732) and ultimately the family comes from a small province in southwestern France called BÃ©arn -- the Capital is Pau (pronounced poh)-- a Protestant stronghold allied to Navarre.
Protestantism had arrived in France in about 1520 and experienced alternating periods of persecution and tolerance. During the years from 1562 until nearly the end of the century, eight civil wars were waged, nominally for religious reasons. The underlying cause however, was rivalry between competing political interests for the French crown.
The Protestants were eventually led by Henry of Navarre, who became Henry IV, King, the first Bourbon ruler of France, after the assassination of the last Valois King in 1589. Although the new King converted to Catholicism to ease the transition, he granted full Protestant tolerance by the Edict of Nantes in 1598.
Peter Crothaire (derivation of de la Croix), a Huguenot of the Bordeaux region (his parents were bÃ©arnais, from the region of BÃ©arn near Navarre), changed his last name to LaRoche (upon marriage?), during his service to the husband of Queen Anne. BÃ©arn was a small semi-independent province, immediately north of the PyrÃ©nÃ©es, about 45 miles long and 35 miles wide. Pau, its capital, lies at the center. It formed a considerable portion of the Kingdom of Navarre. Today Pau is included in the Department of Basses PyrÃ©nÃ©es.
One of the Trustees of Georgia at its founding, John LaRoche, descended from Peter Crothaire nÃ©e LaRoche(see also http://www.cviog.uga.edu/Projects/gainfo/tdgh-nov/nov10.htm
) Another descendant, of a later generation, Isaac LaRoche, was born in Savannah. He became a merchant-farmer in Richmond County, Georgia. Records indicate that his father was a soldier in the American Revolution. Isaac's wife, Elizabeth, was the daughter of another "American" soldier from London, who allegedly provisioned his fighting company out of his own pocket after immigrating to the Augusta area.
She was also the granddaughter of Donald MacKay, who as a child first settled at New Inverness (Darien Ga.) in about 1736. Donald's Scottish father was killed or captured at the battle of Moosa (1740) when Donald was only nine. Donald overcame this tragedy and later owned part of St. Simons Island, including possession of Fort Fredricka, after the Spanish were no longer a threat to English holdings in Georgia. The abandoned tabby (shell concrete) buildings at Fredricka were recycled because of a lack of materials at the time, leaving only the base outlines tourists see today.
Hope that gives you a start