He was the son of George Klock and Margaret Catherine Walrath.[2][3] George Klock was a farmer and trader who kept a disreputable store and tavern next to the Mohawk village of Canajoharie.[4] The Mohawk Canajoharie chief complained to William Johnson "I am under the necessity of complaining again, against that old rogue, the old disturber of our village, George Klock".[5]Joseph Brant and others broke into his house and forced him to relinquish his claim to the Mohawk village of Canajoharie.[4] Jacob Klock married Anna Nelles in Albany County on April 7, 1763.[3]