Pillars of the Earth is an excellent historical drama ... the enormity of constructing a cathedral ... great portrayal of the atmosphere of a tumultuous period of English history known as, The Anarchy in the 12th century. ...set at the time after the death of Henry I during the anarchy and civil war that resulted from the clash between Stephen and Matilda (or Maud as she's called in the movie ) for the right to ascend the throne. There are small inconsistencies.... two-handed swords were used in the 13th - 17th century, not 12th....but certainly doesn't diminish the movie.
It´s quite possible the existence of gaps in 900 years. Also, some branches might had had more females descending from the same ancestor than others and the women then married extremely young. On top, men and women married several times and were extremely prolific, so even among the children of the same parent there were big gaps in age. A difference of four generations -100 years more or less- is not such a great deal going so far back.
By this path Foulques V was the 31st ggf.