Count Eberhard of Nellenburg was a nobleman from the House of Nellenburg, a prominent family in medieval Switzerland. He is known for his role in regional politics during the late 13th century, particularly in the Canton of Thurgau. His leadership contributed to the stability and governance of the area. Eberhard's influence extended beyond local matters, as he was involved in various alliances and conflicts typical of the feudal system. His legacy is reflected in the historical significance of the Nellenburg Castle, which served as a symbol of his family's power and authority in the region.