But in order to root out heresy it was necessary to discover it in its
most secret retreats. The Albigeois had been crushed, but the poison of
their doctrine was not yet destroyed. The organized system of searching
out heretics known as the Inquisition was founded by Pope Gregory IX
about A.D. 1233, and fully established by a Bull of Innocent IV (A.D.
1252) which regulated the machinery of persecution “as an integral part
of the social edifice in every city and every

[58] State.” This powerful engine for the suppression of the freedom of
men’s religious opinions is unique in history.

The bishops were not equal to the new talk undertaken by the Church, and
in every ecclesiastical province suitable monks were selected and to
them was delegated the authority of the Pope for discovering heretics.
These inquisitors had unlimited authority, they were subject to no
supervision and responsible to no man. It would not have been easy to
establish this system but for the fact that contemporary secular rulers
had inaugurated independently a merciless legislation against heresy.
The Emperor Frederick II, who was himself undoubtedly a freethinker,
made laws for his extensive dominions in Italy and Germany (between 1220
and 1235), enacting that all heretics should be outlawed, that those who
did not recant should be burned, those who recanted should be
imprisoned, but if they relapsed should be executed; that their property
should be confiscated, their houses destroyed, and their children, to
the second generation, ineligible to positions of emolument unless they
had betrayed their father or some other heretic.

Frederick’s legislation consecrated the stake as the proper punishment
for heresy. This