The House of Medinaceli is a noble family in Spain, known for its historical significance and vast estates. Founded in the late 15th century, it has played a prominent role in Spanish history, particularly during the Spanish Civil War and the Spanish Empire era. The family has produced numerous influential figures, including politicians and military leaders. The family's lineage includes titles such as the Duke of Medinaceli, which is one of the oldest and most prestigious titles in Spain. The Medinaceli Palace in Madrid and other properties showcase their architectural heritage, reflecting the family's wealth and influence over centuries.