Why did DePaul, a Catholic university, pick a demon as its mascot? Why the DePaul Blue Demons?
The DePaul web site (www.depaul.edu) has the answer. DePaul was founded in 1898, but had no official nickname for three years. In 1901, the university's board of directors first gave letters to players who had played on any varsity sports team for an entire season. The letter given, of course, was a large D.
On campus, students walking around with a D on their sweaters were known as "D-Men." Over the years, "D-Men" evolved into "Demon."
In the 1930s, the school voted to color its mascot blue, to symbolize loyalty, and they have been the DePaul Blue Demons ever since.