Clarendon Co. Genealogy Forum read and post messages about your ancestors for this county
Clarendon County Historical Society
Clarendon County, SC GenWeb Project collection of online resources for genealogy researchers
Clarendon County Surnames
Census-Online.com - census transcriptions for  Clarendon Co.
The Tombstone Transcription Project - cemeteries for Clarendon  Co; SC
US GenWeb Archives for Clarendon County cemeteries, newspapers, wills, military rosters etc recorded online here
World War II Honor List of Dead and Missing Army and Army Air Forces Personnel - Clarendon County

Additional Resources

South Carolina Obituaries enter your South Carolina ancestor's name to search obituaries in over 75 million newspaper pages
South Carolina Birth Records
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South Carolina Death Records