Vindiciae contra tyrannos (meaning: "Defences [of liberty] against tyrants") was an influential Huguenot tract published in Basel in 1579. Its author remains uncertain, since it was written under the pseudonym of "Stephen Junius Brutus". Likely candidates for its authorship include Hubert Languet and Philippe de Mornay. In 1931, Gerardina Tjaberta van Ysselsteyn conjectured that the tract was a collaboration between Languet and de Mornay.