The Empress of the Seven Oceans by Fiona Cooper

'It is the swashbuckling seventeenth century, and witch-burning and superstition are sweeping England. Puritanism and paranoia abound. An old soak salt of a woman named Queenie has to rescue her godchild who has been accused of witchcraft. Queenie steals a boat, The Mermaid's Eye, and takes to the high seas with her goddaughter and her best friend.
'Hounded from their village, Rowan and Esther live deep in the woods. When they are hunted by witchfinders they take to the river, picking up a bewildered nun on the way. All rivers lead to the ocean, where they join Queenie and crew. The Mermaid's Eye becomes The Empress of the Seven Oceans and the women embark on the strangest voyage of all.
'Fiona Cooper has a unique and outrageous voice, and in The Empress of the Seven Oceans she has painted a vivid, hilarious, and ultimately very moving picture of women together.'