Why isn't the ''holy inquision'' in history textbooks?

It is quite likely that the inquisition would not be covered in too much detail in the history text books used by schools because that chapter in the catholic churches history would be something that the catholic church as a whole not to mention Christianity would rather not delve into too deeply. There fore pressure would be brought to bear on governments to limit the coverage of these events in the general education of children. ( and the church has the political clout to do it) In any case none of the churches have a particularly good history in the field human rights and abuse so it seems that there is a general code of silence on the part of all religions.