The Alchemical Marriage

Set in 1588. Sir Adam Macrae, Scottish weather mage and Guardian, hates the English but must stop the Spanish Armada to fulfill his Guardian's oath to protect all of Britain. But he can't do it alone. His only chance is an "alchemical marriage" with mage and refugee Spanish Marrano Isabel de Cortes. Adam and Isabel are ancestors of Duncan and Jean Macrae of A Kiss of Fate and A Distant Magic.