The first details of the Badia di San Salvatore at Spugna date back to the early XI century. The area upon which the Badia rises belonged to the Bishop of Volterra, feudatory of the Holy Roman Empire, but was claimed by the powerful count Ildebrando of the Aldobrandeschi, who, in the meantime, had invaded it. 
Pope Giovanni XVIII himself was forced to intervene to calm the situation, which was settled in the year 1007, with the stipulation of an exchange deed between the two parties.