The castle was home to the Bigods (1100-1306), Thomas Plantagenet and his descendants (1312-1375), the Mowbray Dukes of Norfolk (1375-1481), and the Howard Dukes of Norfolk (1481-1535). All these notable people received high honours from the monarch of their day. Nearly all were Earls Marshal of England and Stewards of the Royal Household. Some, like the 3rd Duke of Norfolk (1472-1554), were much more; he was Lord Treasurer, Earl Marshal, Viceroy of Ireland, Lord High Admiral, Ambassador in Paris, and the richest layman in England.
He lived at Framlingham until 1535 and then built a country seat at Kenninghall near Diss which rivalled Hampton Court. During the time that Framlingham was the key residence of these notable people all roads led to it. It became the economic centre of wide estates, which in the case of the 3rd Duke of Norfolk, involved property in Norfolk, Suffolk, Sussex, Wales, and London.
In the late 14th century £2,000 of goods were being managed each year by the Framlingham warehouses, a vast sum in those days. About 1285 a market was granted by the last Bigod (died 1306) to be held on Tuesdays, Fridays and Sundays. Framlingham expanded and the historic core of the town reached its presents dimensions by 1500.