Is there a way to change a SVN users username through the entire repository history?

Question

When my team first started out with SVN we all just used our first names when committing to the repository, however, now that our team has grown, we are running into issues

Answer 1

In Thunder Below, the story of the USS Barb in WWII, a new officer comes aboard. The Captain asks him his name. "Mike", he responds. "Nope, we already have a Mike", says the Captain. "We'll call you Robert. In combat, when I call out orders, there can be no confusion about who I'm talking to."

What I'm getting at is that there's precedent for making your new Mike choose another name.