Board Thread:Warhammer 40k General Discussion/@comment-203.134.114.240-20130706042929/@comment-3258762-20130716154859

I believe (though I cannot source this or verify if it is canon) that the Force Commander was ordered by Kyras on a 100 years Penance Crusade into the Eye of Terror, and Thaddeus spoke up against it, thus being sent away with the Commander.