Complex sentence: Connected with the Scottish raids of 1322 was the battle of Boroughbridge, in which the Earl of Lancaster was taken prisoner, led from Boroughbridge to his own castle of Pontefract and there beheaded.
Split into simpler sentences: Connected with the Scottish raids of 1322 was the battle of Boroughbridge, in which the Earl of Lancaster was taken prisoner. He was led from Boroughbridge to his own castle of Pontefract and there beheaded.