with Laurie. It may be almost too hard to tell
However, I wonder if it may be the simple iris germanica. I have noticed around here, the most common irises were irises that are super popular historics. If these irises were already on your property, I have a hunch it is highly likely to be whatever the most popular purple that looks like this was at the time it was planted.
Iris germanica fits that bill to me. No way to prove the name without growing an ID next to it and comparing when they bloom.