Definition: In this task, you will be presented with a text and a pronoun. You should write the name that the pronoun refers to. Position of the pronoun in the text is showed within two "_"s.
Input: He marched on Wareham, the port used by Matilda's party to maintain communications with Normandy. Wareham was too strongly defended for the king to capture, so he turned towards Salisbury instead. On his way there, he occupied Wilton Abbey while waiting for reinforcements from Winchester. While King Stephen was stationed at Wilton, mustering _his_ forces for an attack on Salisbury, Earl Robert mounted a surprise attack at sunset on 1 July 1143. Stephen attempted to break out from the siege, but his army was forced back and dispersed by a cavalry charge from Earl Robert's army. <sep>, Pronoun: his

Stephen