What Nobody Told You About Habsburg Inbreeding: When Marrying Cousins Caused Tragedies

The House of Habsburg, one of the most powerful and iconic dynasties in Europe, is known for its grandeur and palace intrigues. However, behind its splendor lies a dark secret: the inbreeding that characterized its marriages, which not only aimed to preserve power but also sowed the seeds of tragedy. In this article, we will explore how marriages between cousins and the obsession with genetic purity led to the downfall of some of the greatest leaders of this royal family.

The Habsburg Marriage Strategy: More Than Love

Since the rise of Philip I of Castile in the 16th century, the Habsburgs adopted a marriage strategy that prioritized politics over feelings. Marrying cousins and other close relatives became one of the most employed tactics to consolidate their dominance in Europe. By uniting kingdoms through marriage, the Habsburgs sought to maintain their influence and power. As the contemporary chronicler Antonio Pérez noted, “the trunk of the Habsburgs is nourished by the blood of its own children.”

The Harmful Effects of Inbreeding: A Tragic Legacy

However, this obsession with maintaining the "purity" of the bloodline had devastating consequences. Inbreeding generated a series of genetic problems that affected many family members. One of the most emblematic examples is Philip II of Spain, who, although he was a powerful king, suffered from multiple health issues and was said to have severe depression, something that could be attributed to the inbreeding in his lineage.

The case of Charles II of Spain, nicknamed “the Bewitched,” is perhaps the most tragic of all. Born in 1661, Charles...