Who is Cob o' Fenton from Katherine and what is their importance?

Cob was a serf from Kettlethrope, Katherines eastate in Linconshire. He had run away. During the peasants revolt Cob finds Katherine exhausted and hids her from the mob. She rewards him for his this by giving him his freedom. On her return to Kettlethrope it is Cob meets her again. He is now the unofficial 'mayor' in Kettlethrope.

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