Originally simply a list of kings with reign lengths , the other details contained in the Poppleton Manuscript version were added in the 10th and 12th centuries .
The list survives in the Poppleton Manuscript , a 13th - century compilation .
Originally simply a list of kings with reign lengths , the other details contained in the compilation   version were added in the 10th and 12th centuries .
The list survives in the Poppleton Manuscript , a 13th - century compilation .