Barty attended Hogwarts School of Witchcraft and Wizardry. Young Barty had achieved twelve O.W.L.s, though Crouch was delirious when claiming it. It is very likely that he knew many other Death Eaters and their allies at school, such as Severus Snape, Regulus Black and Lucius Malfoy.
HufflepuffAlastor “Mad-Eye” Moody is a Hufflepuff. That idea always seems to get the most pushback, but I stand by it. As a proud Hufflepuff myself, I may be a little biased. I would love to claim every unsorted character for my own House, the best of the four.