I'm referring to the belief held today by some Christian creationists. When, where, and from whom did this calculation of earth's age originate? Did Jews in the time of Christ think of earth as being ~4000 years old, or was this number the product of later theologians or historians?
This chronology comes from a 17th Century Anglican Bishop named James Ussher. He basically counted up all the begets and begots and concluded that the earth was created on October 23, 4004 BC.
There were some others before Ussher who tried to do similar calculations and came up with similar dates (Kepler is one), but Ussher's chronology has become the classic YEC model.