church of secular canons at Southwell. In 1191, he was allowed to cede half to his nephew Reginald. Vacarius is last heard of in 1198, when he and the prior of Thurgarton were commissioned by Pope Innocent III to fulfill a letter referring to crusades. In addition to his legal work, surviving manuscripts attest to Vacarius' deliberations on other matters as well, likely in the latter half of his life. One of these, the Summa de assumpto homine, deals with the humanity of Christ, while the other, Summa de matrimonio, is a legal argument about the nature of marriage, in which he disputes both Gratian and Peter Lombard. It is to Vacarius that we owe most of the information that has come down to us about Speroni, a heretic from Piacenza. Notes References * 12th-century Roman Catholics English legal professionals Italian legal scholars Legal historians Canon law jurists 12th-century Italian jurists Legal scholars of the University of Oxford 1120 births 1200 deaths Year of death uncertain