Trying to create a new database user

Hi, I'm on Debian 8 currently with Postgres 9.4.12. I'm trying to create a new user brian by using various createuser commands, or creating roles right in psql, but for whatever reason unless there is a database called, brian, I cannot log in as that user.

Is this normal? Without the database, trying to use the command, psql -W -U brian simply tells me,

psql: FATAL:  database "brian" does not exist