Conversation so far:
What did Matthew Paris do as a historian?
Matthew Paris wrote a number of works, mostly historical, which he scribed and illuminated himself, typically in drawings partly coloured with watercolour washes, sometimes called tinted drawings.
What was the history that Matthew Paris' predecessors had followed?
After admission to the order in 1217, Matthew Paris inherited the mantle St. Albans' official recorder of events, in 1236.

Question: What did he write about?
Self-contained rewrite: what did Matthew Paris write about?