SVN cannot authenticate using Negotiate

I am getting an error when I try to checkout my repositories:

Unable to access [url removed] : svn: E170001: Negotiate authentication failed: 'No valid credentials provided'

I have supplied credentials through Jenkins; on the command-line, I can checkout the exact url it's pointed at using the exact credentials specified simply as username and password arguments. I have also tried adding "Additional Credentials", but that doesn't help. Storing credentials for command-line svn did not help, nor did removing the entire credentials store for user Jenkins in case that was interfering.