Lesbianism (female homosexuality) in pre-modern Spain (1200 - 1813) was largely not tolerated and considered illegal, with a possible death punishment. During this period, Spain's legal and religious justice systems were at times one and the same, with female homosexuals being persecuted by both civil and religious authorities. In 1497, Spain's Catholic monarchs Isabel and Fernando said anyone who engaged in unnatural sex should be given the death penalty. Spanish lesbians were caught up in the Inquisition, with documented cases of some of them having been burned at the stake. During confessions, priests were often interested in women's sex acts.
Medical texts began to develop in this period to try to explain female sexual desire for other women. One explanation was that these women should have been born men, but the mother did something wrong and their sex changed while they were in the womb. Women in this period who expressed desire for other women were most often found in convents or working as prostitutes. Some women in Spanish prisons engaged in sodomy, but this was allegedly because they lacked male sexual partners.
Prominent female homosexuals of the period included Katalin Erauso, Isabel de Borbón-Parma, and Elena/o de Céspedes . Important Sapphic writers included María de Zayas and Teresa de Avila. Notable literary works depicting female homoeroticism include Tirant lo Blanc, originally published around 1490 and written by Joanot Martorell and Martí Joan de Galba, and La Celestina is a Spanish novel attributed to Fernando de Rojas. A number of modern words associated with lesbianism in Spain originate from this time period including tortillera, desviada, marimacho, tríbada and virago.