Background
Leonor was the paternal great-granddaughter of Garci Lasso de la Vega I, the chancellor of the Kingdom of Castile, who was executed in 1326 by order of King Alfonso XI of Castile, and his wife Juana de Castañeda. She was the paternal granddaughter of Garci Lasso de la Vega II, assassinated by Peter of Castile in 1351, who was the highest royal official to the court of Fadrique Alfonso de Castilla, son of King Alfonso XI of Castile, and his wife, Leonor González de Cornado. She was the only daughter of Garci Lasso Ruiz de la Vega, who spent his life in the service of Henry II of Castile and was killed at the Battle of Nájera in 1367 whereupon Leonor rose to the position of head of house.
Career
Leonor"s first marriage was with Juan Téllez de Castilla, the second lord of Aguilar de Campoo and the second lord of Castañeda. He was the son of Tello de Castilla who was in turn, the illegitimate son of Alfonso XI of Castile and Leonor de Guzmán. The couple had the following children:
Aldonza Téllez de Castilla y de la Vega (b 1382 - d 1449), who married Garci IV Fernández Manrique de Lara.
The couple went on to become the first Condes de Castañeda.
Their offspring went on to found the Marquesado de Aguilar de Campoo, the Ducado de Galisteo and the Condado de Osorno. When Tello died on August 14, 1385 at the Battle of Aljubarrota, Leonor remarried in 1387 with Diego Hurtado de Mendoza, High Admiral of Castile, bringing with her dowry, the title over the town of Carrión de los Condes and a manor at Asturias de Santillana.
The two had the following children:
García Lasso de la Vega, who according to his father"s testamentary clauses had to change his name to Juan Hurtado de Mendoza. Elvira Laso de Mendoza, married Gómez I Suárez de Figueroa, first head of the House of Feria, son of Lorenzo I Suárez de Figueroa, Grand Master of the Order of Santiago.
The couple were parents of, amongst others, Lorenzo II Suárez de Figueroa, first Conde de Feria.
Gonzalo Ruiz de Mendoza, whose grandmother, Mencía de Cisneros in her last will and testament of 1380 left him titles over Tierra de Campos and Vega with all its land and vassals. Teresa de la Vega y Mendoza, married Álvaro Carrillo de Albornoz. After her death, all her domains went to the House of Mendoza through Íñigo López de Mendoza.
In 1445 King, John II of Castile confirmed this action by granting the title of Marquis of Santillana, where after Santillana del March which became the center of the lordship of Torrelavega in Cantabria.
The Cantabrian surname "Lasso de la Vega" was passed on through this maternal line at later times throughout the years and is associated with various soldiers, poets, and golden age writers such as Garcilaso de la Vega, the soldier and poet, and Inca Garcilaso, the historian from the Viceroyalty of Peru.
