Which council specifically addressed the Arian controversy?

The First Council of Nicaea, held in 325 AD, is primarily recognized for addressing the Arian controversy, which revolved around the nature of Christ and his relationship to God the Father. Arius, a priest from Alexandria, claimed that the Son (Jesus Christ) was not co-eternal with the Father and was therefore a created being. This doctrine challenged fundamental Christian beliefs about the Trinity.

At the Council of Nicaea, bishops from various regions came together to confront the teachings of Arius and to establish a unified Christian doctrine. This led to the formulation of the Nicene Creed, which articulated the belief in the consubstantiality of the Son with the Father, affirming that Jesus is "true God from true God" and was not created but begotten. The council played a crucial role in clarifying the orthodox Christian belief about the Trinity and provided a framework for addressing heresies in the future.

The other councils listed did not focus on the Arian controversy; rather, they dealt with different theological disputes or issues in the Church, making the First Council of Nicaea the definitive answer regarding the Arians.