Pate was a novice studying to become a maester at the Citadel in Oldtown. He was not believed to be very intelligent; he had been at the Citadel for five years but had not earned a single link for his maester's chain. Part of his duties included looking after old senile Archmaester Walgrave.
He was also a patron of the Quill and Tankard inn, and was in love with the innkeeper's daughter, Rosey. With his studies not proceeding well, Pate agreed to steal a key that would open every door in the Citadel for a man known as 'the alchemist' in return for money. Specifically, he promised Pate a golden dragon if he brought him the personal key of Walgrave in three days. Pate thinks about this offer for two days. He needs the gold to claim the maidenhood of Rosey.
Having performed this service, Pate was then killed by the alchemist, who expressed regret for the necessity. Later, someone claiming to be Pate and matching his description was revealed to be in the service of Archmaester Marwyn and an associate of Alleras the Sphinx, although it is unconfirmed if it was really him or an imposter.