William made the church subordinate to him. Bishops were elected only subject to the King's consent. Homage was exacted from them. William imposed knight's service on bishoprics, abbeys, and monasteries, which was commuted to a monetary amount. Bishops had to attend the King's court. Bishops could not leave the realm without the King's consent. No royal tenant or royal servant could be excommunicated, nor his lands be placed under interdict, without the King's consent. Interdict could demand, for instance, that the church be closed and the dead buried in unconsecrated ground. No church rules could be made without his agreement to their terms. No letters from the Pope could be received without the King's permission. Men continued to give land to the church for their souls, such as this grant which started the town of Sandwich: "William, King of the English, to Lanfranc the Archbishop and Hugoni de Montfort and Richard son of Earl Gilbert and Haimo the sheriff and all the thegns of Kent, French and English, greeting. Know ye that the Bishop of Bayeux my brother for the love of God and for the salvation of my soul and his own, has given to St. Trinity all houses with their appurtances which he has at Sandwich and that he has given what he has given by my license." When the land was all divided out, the barons had about 3/7 of it and the church 2/7. The King retained 2/7, including forests for hunting, for himself and his household, on which he built many royal castles and hundreds of manor houses throughout the nation. He built the White Tower in London. He and his household slept on the upper floors and there was a chapel on the second floor and a dungeon below the first floor for prisoners. The other castles were often built at the old fortification burhs of Alfred. Barons and earls had castle-guard duty in them. William was constantly moving about the land from castle to castle, where he entertained his magnates and conducted public business, such as deciding disputes about holding of land. Near these castles and other of his property, he designated many areas as royal hunting forests. Anyone who killed a deer in these forests was mutilated, for instance by blinding. People living within the boundaries of the designated forestland could no longer go into nearby woods to get meat or honey, dead wood for firing, or live wood for building. Swineherds could no longer drive pigs into these woods to eat acorns they beat down from oak trees. Making clearings and grazing livestock in the designated forestland were prohibited. Most of the nation was either wooded or bog at this time.