Complex sentence: Some historians contend that the 1521 Spanish expedition led by Francisco Girebillo must have encountered a Waccamaw village when they traveled inland from the Carolina coast along the Waccamaw and Pee Dee rivers.
Split into simpler sentences: Some historians contend that the 1521 Spanish expedition led by Francisco Girebillo came across a Waccamaw village. Girebillo traveled inland from the Carolina coast and along the Waccamaw and Pee Dee rivers.