[1][2] In 1093, Arnulf of Montgomery built the first castle at the site when he fortified the promontory beside the Pembroke River during the Norman invasion of Wales.

He soon became Lord Marshal of England, and set about turning the earth and wood fort into an impressive Norman stone castle.

A 55-step spiral staircase was also created that led down to a large limestone cave, known as Wogan Cavern, beneath the castle.

Although only made from earth and wood, Pembroke Castle resisted several Welsh attacks and sieges over the next 30 years.

When William Rufus died, Arnulf de Montgomery joined his elder brother, Robert of Bellême, in rebellion against Henry I, William's brother and successor as king; when the rebellion failed, he was forced to forfeit all his British[clarification needed] lands and titles.

By 1138 King Stephen had given Pembroke Castle to Gilbert de Clare who used it as an important base in the Norman invasion of Ireland.

In August 1189 Richard I arranged the marriage of Isabel, de Clare's granddaughter, to William Marshal who received both the castle and the title, Earl of Pembroke.

[4] Pembroke Castle became de Valence's military base for fighting the Welsh princes during the conquest of North Wales by Edward I between 1277 and 1295.

In 1389, 17-year-old John Hastings died in a jousting accident, ending a line of inheritance stretching back 250 years.

However, Pembroke escaped attack because the castle's Constable, Francis а Court, paid off Glyndŵr in gold.

Tudor brought his widowed sister-in-law, Margaret Beaufort, to Pembroke where, in 1457, she gave birth to her only child, who was to become King Henry VII of England.

It was besieged by Royalist troops but was saved after Parliamentary reinforcements arrived by sea from nearby Milford Haven.

After his death, a trust was set up for the castle, jointly managed by the Philipps family and Pembroke town council.

In July 2022, archaeological survey funded by the Natural History Museum and the British Cave Research Society uncovered evidence of prehistoric megafauna such as reindeer and woolly mammoth bones, in addition to seashells, pigs and deer at Wogan Cavern.