The Impregnable City

Bristol loomed large in the civil wars of the 12th century. Its massive castle played a key role in the Empress Matilda's challenge to her cousin King Stephen.

Chris Molan depicts Bristol Castle in its heyday, around 1300.

Chris Molan depicts Bristol Castle in its heyday, around 1300.

Now the city has grassy banks where once its castle stood. If you wander around Castle Park you will come across fragments here and there of Bristol's former stronghold.

Bristol was well-sited for defence. It stood on a natural tongue of land almost encircled by the rivers Frome and Avon. To control the town, the Normans had only to guard the narrow approach between the rivers. There they built a motte-and-bailey castle. These fortresses thrown up to cow the newly-conquered land were made of timber. As Norman rule consolidated, many timber castles were replaced by stone keeps. Few rivalled the great keep of Bristol, built by Robert, illegitimate son of Henry I.

Henry had many children by various mistresses, but Robert was his favourite. The king chose a beautiful heiress as Robert's wife. Mabel was the daughter of Robert Fitzhamon, who owned a generous swathe of Gloucestershire, including Bristol. Mabel brought this great estate to her husband, who gained a title to go with it in 1121. He was created Earl of Gloucester.

By that time the succession to the throne was in crisis. For all his many bastards, Henry I had managed to produced only one legitimate son - William. When William drowned in the White Ship in 1120, Henry was bereft. He was already a widower. The king married again, but as the years went by and Queen Adelaide produced no child, Henry began to focus his hopes on his one legitimate daughter Matilda.

Princesses were pawns in medieval politics. When barely out of childhood Matilda was thrust into marriage to the Emperor of Germany. When the emperor died, Henry arranged another marriage for her, which he hoped would cement peace with an old enemy. Her new husband was to be Geoffrey, son of the Count of Anjou.

Having his daughter by his side between marriages, the king took an extraordinary step. At Christmas 1126 Henry summoned the clergy and nobility to London and made them swear that if he died without a male heir, they would accept Matilda as their queen. But the barons were dubious about a woman as ruler. They were also wary of Anjou. So when Henry I died in 1135, his nephew Stephen of Blois gathered enough support to be crowned king. Matilda was determined to do battle for the kingdom.

Robert, Earl of Gloucester, became her trusted right-hand man - the commander of her troops. Earl Robert raised a rebellion in Normandy, while in England rebels rallied to his castle at Bristol. Stephen reconnoitred Bristol and contemplated a seige, but gave up the idea as impractical. Bristol was impregnable. Instead Stephen strengthened Bath's fortifications and left a garrison there to keep a check on Bristol.

Earl Robert escorted his sister to England in September 1139. They landed at Arundel. Leaving Matilda at the castle there with her step-mother Adelaide, Earl Robert slipped away by a hidden byway, eluding Stephen's troops to reach the safety of Bristol. Stephen then decided that he might as well allow Matilda to join her brother, rather than split his forces attacking them separately.

War raged up and down the land. In a dramatic turn of events in February 1141, Stephen was captured and imprisoned in Bristol Castle. Matilda's cause had nearly triumphed. Then in a reversal of fortune, Earl Robert was captured later that year. What could Matilda do but exchange prisoners? So the war dragged on, exhausting the country.

Earl Robert made Bristol Castle his chief residence for the rest of his life. It was so secure that Matilda sent her nine-year-old son Henry there in 1143 to further his education. When Robert died in 1147, Stephen lost his most dangerous enemy.

Still Bristol Castle was staunchly held for Matilda by Robert's son William, Earl of Gloucester. So when young Henry returned to England in 1149, he made his way secretly to Bristol, before slipping out of the country again. He was already Duke of Normandy and inherited his father's domains in 1151. So young Henry was a force to be reckoned with. He invaded England in January 1153. By November Stephen was ready to make peace. Matilda would never reign, but her son would. Stephen adopted Henry as his son and heir. The civil war was over.

Peter Fleming, Bristol Castle: A political history (2004) is the most recent study of the castle's history.