Ulrich II died in 1279 and his guardian Hartmann in 1280, allowing Eberhard to exercise unrestricted reign of the County of Württemberg from 1280.

Rudolph's aim was to re-establish the Duchy of Swabia, which had been leaderless after the execution in 1268 of Conradin, the last member of the Hohenstaufen dynasty.

Despite being weaker, he managed exploit the situation after Rudolph's death in 1291 and achieve military successes against Albert II of Hohenberg-Rotenburg.

Vogt Konrad IV von Weinberg, who acted on the orders of Henry VII, declared war on Eberhard, causing much distress in Württemberg.

Württemberg was saved from defeat by the death of Henry VII on 24 August 1313 and the 1314 elections Louis IV and Frederick the Fair as rival kings.

His participation in the war in Bohemia brought in additional funding, which he used to purchase land and towns in Swabia from impoverished noble families, for example, the count palatine of Tübingen.

The fact that his son Ulrich III acquired Sigmaringen in 1325 and that his daughter Agnes married Count Henry of Werdenberg-Sargans-Trochtelfingen both point to a close relationship between Eberhard and the Werdenberg dynasty.