In 1136, during a period of civil war, Gwenllian ferch Gruffydd leads a Welsh army against the Normans – but she is betrayed by one of her own people, captured, and beheaded.
She is transported to the mythical kingdom of Annwn. There, she meets other characters from Welsh history and mythology, who become her friends and family. Together, they watch as history unfolds in the country they love.
Meanwhile, a mortal child called Lili grows up in a modern village in Wales. She may seem unremarkable, but she and her family members will play a significant role in the destiny of Gwenllian and her companions. They must help her overcome the struggle of being bullied – but will they be able to complete their task?
From the Norman invasion of Britain, through the industrial revolution and miners’ strikes, and up to the tragic events of 9/11, My Name is Gwenllian shows how both the large and the small events throughout history impact ordinary people, and how important it is to have hope.