The letters in Volume 12 cover Erasmus' correspondence for all of 1526 and around the first quarter of 1527. This was a difficult period for Erasmus owing to two bouts of illness serious enough to cause him to draw up his first will in January 1527, and the fact that the Reformers were gaining more and more influence over religious policy in Basel, where he resided. Fearing that the Lutherans might gain complete control of public discourse on the disputed issue of free will, Erasmus rushed to complete his rebuttal to Luther's De Servo Arbitrio in March 1526. He also felt deeply aggrieved by the attacks launched against him by conservative Catholics at a time when he was actively engaged in opposing the spread of heresy in Germany and Switzerland. The letters of 1526-1527 also reflect Erasmus' growing fame in Spain, where not only the Latinate intellectuals but also readers of the new Spanish translations of his spiritual writings and satirical works were attracted to his ideas of spiritual renewal. This publication is supplemented with translations of his earliest will and selections from correspondence among his Spanish admirers during the years 1522-1527.
An appendix analyzes the purchasing power of money in the period 1500-1540.