Introduction
The largely unexplored history of identity intelligence (I2) reveals that it has three prerequisites that did not exist before the 20th century: (1) One or more reliable and immutable identity attributes that can travel with an individual; (2) A sophisticated method of information retrieval; (3) A robust administrative state, with a professional and incorruptible bureaucracy that can consistently collect, retrieve, and employ I2 with accuracy and integrity. I2 cannot function without these three pillars, and wherever and whenever one of them falls short, I2 falls short as well.