Some people say that Cornwall is just another part of England. But is it really?Seamas Carey looks at the hidden history and asks why it was never taught to him at school?From the early celts, to the prayer book rebellion, Episode 4 proves that Cornwall does have a rich past with a distinct identity. But why did the Cornish language (Kernewek) decline, who revived it and how far did the Cornish people travel during the 19th century, when the mining industry spread across the world?