Events from 1537

Pope Paul III confirms Jesuits informally - Ignatius's vision at La Storta: God the Father speaks: 'I will be favorable to you in Rome' - Christ appears: 'I want you to serve Me'

Cosimo I de' Medici becomes Duke - from junior branch, will become Grand Duke of Tuscany

Paracelsus writes treatise on syphilis, recommending mercury treatment and rejecting prevailing guaiac wood remedy

Alessandro de' Medici assassinated by cousin Lorenzino - called 'the Tyrant', last of main Medici line