Elspeth is one of those names that never quite made it out of the British Isles--particularly Scotland, but possesses a winningly childlike charm. Elspeth was used by Sir Walter Scott for several of his female characters.
Elspeth Huxley was a prolific Kenyan-born U.K. writer, best known for the autobiographical The Flame Trees of Thika--she was connected by marriage to the illustrous Huxley family.
A close cousin is Elsbeth, as in the recurring character Elsbeth Tascioni on The Good Wife. Embeth is a more distant relation.