The Lordship of Utrecht was formed in 1528 when Charles V of Habsburg conquered the Bishopric of Utrecht, during the Guelders Wars. In 1528, at the demand of Henry of the Palatinate, Prince-Bishop of Utrecht, Habsburg forces under Georg Schenck van Toutenburg, liberated the Bishopric, which was occupied by the Duchy of Guelders since 1521-1522. On October 20, 1528, Bishop Henry handed over power to Charles of Habsburg. The Bishopric of Utrecht came to an end and was divided into the Lordship of Utrecht and the Lordship of Overijssel, both ruled by a Habsburg Stadtholder. Between 1528 and 1584 the Stadtholder of Utrecht was the same as the Stadtholder of the County of Holland. The Lordship became part of the Burgundian Circle by the Pragmatic Sanction of 1549, and one of the Seventeen Provinces. During the Eighty Years' War, Utrecht joined the revolt against Charles's son Philip II of Spain from the beginning. It was at the center of the Union of Utrecht in 1579 . When the Batavian Republic was created in 1795, the Lordship of Utrecht was abolished.
Question: How many years was the Bishopric occupied by the Duchy of Guelders?
Answer: 1