Hĕrt-surt is the Chuvash spirit of the hearth and the protector of the household. Conceived chiefly in female form and most often as an invisible presence, she keeps the dwelling warm, orderly and prosperous, and is counted among the benevolent terrestrial guardians of the home. Households maintained her goodwill with small offerings and observances, and the cult of the domestic spirits survived into the modern period, particularly among the Chuvash of the Ulyanovsk region. She is a guardian numen of a single house rather than a cosmic deity, and stands apart from the heavenly powers and the grove-spirits, belonging instead to the intimate religion of the farmstead and the family hearth.