The Old Palace at Hatfield was originally the home of the Bishops of Ely. It came into royal posession during the dissolution in the reign of Henry VIII, who then used the palace as a residence for the royal children.

The Old Palace is probably most associated with the Princess Elizabeth, who lived there on and off for the first 25 years of her life. And, it was while in residence at Hatfield that Elizabeth was told of her sister Mary's death and that she was the new Queen of England. The oak tree that the new Queen was sitting under in the park when she received the news has since fallen, but Elizabeth II planted a new one of the site. Elizabeth I held her first council in the great hall, which still survives and is used for Renaissance banquets.

Only one wing of the Old Palace survives, since most of it was torn down to make room for the new house that Robert Cecil began in 1608. Robert was the son of William Cecil, Elizabeth I's most trusted aide.

Many Tudor artifacts can be seen on display at the house, including Elizabeth I's silk stockings, hat and gloves. Many letters associated with the Tudor are there, such as the one where Henry VIII explains his displeasure with his new wife, Anne of Cleves. Several portraits of the Tudors are displayed at Hatfield, most famously the Ermine and Rainbow portraits of Elizabeth I.

The parish church at Hatfield has parts of its structure dating from the early thirteenth century. The building has been added to and remodeled ever since. Robert Cecil, the builder of Hatfield House is buried in the Salisbury Chapel at the church.