The Butcher's Daughter (A Journey Between Worlds) - Captain Mary, the Queen's Privateer, #1

In an age ruled by iron men, in a world of new discovery and Spanish gold, a young Irishwoman named Mary rises from the ashes of her broken childhood with ships and men-at-arms under her command. She and her loyal crew prowl the Caribbean and prosper in the New World for a time until the ugly past Mary has fled from in the old one finds her. Across the great ocean to the east, war is coming. The King of Spain is assembling the most powerful armada the world has ever seen - an enormous beast - to invade England and depose the Protestant "heretic queen." To have any chance against the wealth and might of Spain, England will need every warship, she will need every able captain.
To this purpose, Queen Elizabeth spares Mary from the headman's axe for past sins in exchange for her loyalty, her ships and men. Based on true historical events, this is an epic story about war, adventure, love and betrayal. This is a timeless story about vengeance. This is a tale of heartbreak.