[1] Guglielmo's chronicle informs us that he had turned fifty by 1300 and sixty by 1310.
[2] He became merchant of spices, was a member of the bourgeois popolo and held several important municipal offices.
[2] Guglielmo wrote a chronicle of the city, the Memoriale de rebus gestis civium astensium et plurium aliorum,[a] covering the years 1261–1325, although the last few years were added by another hand.
The Memoriale is written in ungrammatical Latin prose and divided into 114 chapters.
[1] The Memoriale is especially valuable today for its length, detail and general accuracy, although Guglielmo uncritically records traditions and legends.