Cressida grew up in London and on a small, uninhabited island off the west coast of Scotland. The island had no roads, houses or electricity. For the first four years, the family would be dropped off like castaways on the island by a local boatman and picked up again two weeks later. Imagine being like Robinson Crusoe and having a whole island to yourself to explore

By the time Cressida was eight, the family had built a small stone house on the island, so they no longer had to camp out in tents, which made life much drier. Her father got a boat, so they could fish for enough food to feed the family for the whole summer. Every year, Cressida spent the long summer holiday, and some of the spring, on the island. The house was lit by candle-light, and there was no electricity, telephone or television, so Cressida and the family lived like people in the olden days. In the evening, Cressidas father told the children old Scottish tales about the people who lived on the surrounding islands, who were always fighting and tricking each other, and about dragons living in caves in the cliffs.

Cressida spent her time writing stories, fishing for things to eat, and exploring the island looking for these dragons. These childhood experiences (quite apart from her fluency in Old Norse, of course), made her delighted to be approached to translate the Hiccup memoirs.

After school, Cressida obtained a BA in English Literature from Oxford University, a BA in Graphic Design from St Martins and an MA in Narrative Illustration from Brighton. Cressida wrote and illustrated her first picture book, Little Bo Peeps Library Book for Hodder Childrens Books in 1998. She loves to write picture books and her Emily Brown series, illustrated by Neal Layton, was winner of the 5 and Under category of the Nestlé Childrens Book Prize 2006. Her first novel for eight to twelve year olds, How to Train Your Dragon, was published to popular and critical acclaim in 2003.

Cressida is married to Simon Cowell (who is not THAT Simon Cowell, but a quite different Simon Cowell). They live in London with their three children, Maisie, Clementine and Alexander.