Question: Where was the place of death of Helena (Empress)'s husband?

Knowledge 1: Helena (empress)
Helena, or Saint Helena(Greek: Ἁγία Ἑλένη, "Hagía Helénē", ; c. 246/248 –), was an Empress of the Roman Empire, and mother of Emperor Constantine the Great.Born outside of the noble classes, a Greek, possibly in the Greek city of Drepana, Bithynia in Asia Minor, she became the of the future Roman Emperor Constantius Chlorus and the mother of the future Emperor Constantine the Great.Helena ranks as an important figure in the history of Christianity and of the world due to her influence on her son.In her final years, she made a religious tour of Syria Palaestina and Jerusalem, during which ancient tradition claims that she discovered the True Cross.The Eastern Orthodox Churches, Oriental Orthodox Churches, Roman Catholic Church, and the Anglican Communion revere her as a saint; the Lutheran Church commemorates her. [SEP] Knowledge 2: Constantius Chlorus
Constantius I (31 March 25 July 306), commonly known as Constantius Chlorus ("Kōnstantios Khlōrós", literally "Constantius the Pale"), was a Caesar from 293 to 305 and a Roman Emperor from 305 to 306.He was the father of Constantine the Great and founder of the Constantinian dynasty.As "Caesar", a junior emperor, he defeated the usurper Allectus in Britain and campaigned extensively along the Rhine frontier, defeating the Alamanni and Franks.Upon becoming "Augustus" in 305, Constantius launched a successful punitive campaign against the Picts beyond the Antonine Wall.However, Constantius died suddenly in Eboracum (York)the following year.His death sparked the collapse of the tetrarchic system of government inaugurated by the Emperor Diocletian.
Knowledge 1: Helena (empress)
Helena, or Saint Helena(Greek: Ἁγία Ἑλένη, "Hagía Helénē", ; c. 246/248 –), was an Empress of the Roman Empire, and mother of Emperor Constantine the Great.Born outside of the noble classes, a Greek, possibly in the Greek city of Drepana, Bithynia in Asia Minor, she became the of the future Roman Emperor Constantius Chlorus and the mother of the future Emperor Constantine the Great.Helena ranks as an important figure in the history of Christianity and of the world due to her influence on her son.In her final years, she made a religious tour of Syria Palaestina and Jerusalem, during which ancient tradition claims that she discovered the True Cross.The Eastern Orthodox Churches, Oriental Orthodox Churches, Roman Catholic Church, and the Anglican Communion revere her as a saint; the Lutheran Church commemorates her. [SEP] Knowledge 2: John Patrick Carroll
John Patrick Carroll (Dubuque, Iowa, 22 February 1864 – Switzerland, 2 November 1925) was an American Catholic priest, who became the second Bishop of Helena, Montana,U.S.A. He was ordained a priest for the diocese of Cleveland on 7 July 1889 and was consecrated the second Bishop of Helena on 21 December 1904.
Knowledge 1: Helena (empress)
Helena, or Saint Helena(Greek: Ἁγία Ἑλένη, "Hagía Helénē", ; c. 246/248 –), was an Empress of the Roman Empire, and mother of Emperor Constantine the Great.Born outside of the noble classes, a Greek, possibly in the Greek city of Drepana, Bithynia in Asia Minor, she became the of the future Roman Emperor Constantius Chlorus and the mother of the future Emperor Constantine the Great.Helena ranks as an important figure in the history of Christianity and of the world due to her influence on her son.In her final years, she made a religious tour of Syria Palaestina and Jerusalem, during which ancient tradition claims that she discovered the True Cross.The Eastern Orthodox Churches, Oriental Orthodox Churches, Roman Catholic Church, and the Anglican Communion revere her as a saint; the Lutheran Church commemorates her. [SEP] Knowledge 2: John Patrick Carroll
John Patrick Carroll (Dubuque, Iowa, 22 February 1864 – Switzerland, 2 November 1925) was an American Catholic priest, who became the second Bishop of Helena, Montana,U.S.A. He was ordained a priest for the diocese of Cleveland on 7 July 1889 and was consecrated the second Bishop of Helena on 21 December 1904.

Answer: Eboracum