Alba
The ruler of Alba was King Constantine I (Constantine the Wine-Bountiful), who had ruled since 862 and would continue to do so until 877.
Mercia
The ruler of Mercia at the beginning of 874 was King Burgræd, who had ruled since 842. This year, King Ceolwulf II would take over.
Strathclyde
The ruler of Strathclyde at this time was likely to have been King Rhun map Arthgal.
Wessex
The ruler of Wessex was King Ælfræd (Alfred the Great), who had ruled since 871 and would continue to do so until 899.