John treated the interdict as "the equivalent of a papal declaration of war". He responded by attempting to punish Innocent personally and to drive a wedge between those English clergy that might support him and those allying themselves firmly with the authorities in Rome. John seized the lands of those clergy unwilling to conduct services, as well as those estates linked to Innocent himself; he arrested the illicit concubines that many clerics kept during the period, only releasing them after the payment of fines; he seized the lands of members of the church who had fled England, and he promised protection for those clergy willing to remain loyal to him. In many cases, individual institutions were able to negotiate terms for managing their own properties and keeping the produce of their estates. By 1209 the situation showed no signs of resolution, and Innocent threatened to excommunicate John if he did not acquiesce to Langton's appointment. When this threat failed, Innocent excommunicated the king in November 1209. Although theoretically a significant blow to John's legitimacy, this did not appear to greatly worry the king. Two of John's close allies, Emperor Otto IV and Count Raymond VI of Toulouse, had already suffered the same punishment themselves, and the significance of excommunication had been somewhat devalued. John simply tightened his existing measures and accrued significant sums from the income of vacant sees and abbeys: one 1213 estimate, for example, suggested the church had lost an estimated 100,000 marks (equivalent to £66,666 at the time) to John. Official figures suggest that around 14% of annual income from the English church was being appropriated by John each year.
When did Innocent excommunicate the king?
November 1209