When Vicki Pallister and Steven Taylor were captured by Eldred, he questioned them. Based on his wife's account of her meeting with the First Doctor, he believed their claim that they were just travellers, despite Eldred's protests. He had Edith give them food for their journey.
He believed the Monk's story of ships coming with supplies, and agreed to set up a beacon for them, not knowing they were in reality a Viking fleet. However, Edith told him that the Doctor had warned her that a Viking fleet was coming. When Eldred returned from the monastery reporting the presence of Vikings, Wulnoth led his village in defending against the Viking attack. (TV: The Time Meddler)