Britannia Secunda was one of the provinces of Roman Britain

Roman Britain

Roman Britain was the part of the island of Great Britain controlled by the Roman Empire from AD 43 until ca. AD 410.The Romans referred to the imperial province as Britannia, which eventually comprised all of the island of Great Britain south of the fluid frontier with Caledonia...

 in existence by c. 312 AD and probably created as part of the administrative reforms of the Roman Emperor Diocletian

Diocletian

Diocletian |latinized]] upon his accession to Diocletian . c. 22 December 244  – 3 December 311), was a Roman Emperor from 284 to 305....

 after the defeat of the usurper Allectus

Allectus

Allectus was a Roman usurper-emperor in Britain and northern Gaul from 293 to 296.-History:Allectus was treasurer to Carausius, a Menapian officer in the Roman navy who had seized power in Britain and northern Gaul in 286...

 by Constantius Chlorus

Constantius Chlorus

Constantius I , commonly known as Constantius Chlorus, was Roman Emperor from 293 to 306. He was the father of Constantine the Great and founder of the Constantinian dynasty. As Caesar he defeated the usurper Allectus in Britain and campaigned extensively along the Rhine frontier, defeating the...

 in 296 AD. The governors of Britannia Secunda were of equestrian rank although few are known by name. Their capital was at York

York

York is a walled city, situated at the confluence of the Rivers Ouse and Foss in North Yorkshire, England. The city has a rich heritage and has provided the backdrop to major political events throughout much of its two millennia of existence...

. The province is named in the Verona List

Verona List

The Laterculus Veronensis or Verona List is a list of Roman provinces from the times of the Roman emperors Diocletian and Constantine I. The list is transmitted only in a 7th-century manuscript, which is preserved in the Chapter House Library in Verona. The most recent critical edition is that of...

 and probably encompassed all of what is now northern England

England

England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

 and possibly north Wales

Wales

Wales is a country that is part of the United Kingdom and the island of Great Britain, bordered by England to its east and the Atlantic Ocean and Irish Sea to its west. It has a population of three million, and a total area of 20,779 km²...

. In 369

369

Year 369 was a common year starting on Thursday of the Julian calendar. At the time, it was known as the Year of the Consulship of Galates and Victor...

, a new province of Valentia

Valentia (Roman Britain)

Valentia was the name of a consular northern province of Roman Britain.-History:Count Theodosius set up Valentia in 369 AD as part of his reorganisation of Britain following the Great Conspiracy, and probably named it after the reigning emperors, Valentinian and Valens.Ammianus tells of how the...

was created, probably from a portion of Britannia Secunda.