Saint Isidore of Seville (560 - April 4, 636) was Archbishop of Seville for more than three decades and has the reputation of being one of the great scholars of the early middle ages. All the later medieval history-writing of Spain was based on Isidore's histories. Isidore's most important work was the first encyclopedia known to be compiled in western civilization, the Etymologiae. The encyclopedia was a huge compilation of 448 chapters in 20 volumes, devoted to transmitting the epitome of the learning of antiquity. He was canonized as a saint by the Roman Catholic Church in 1598 and declared a Doctor of the Church in 1722.