In 2005, John Darnielle released The Sunset Tree. The Mountain Goats made their first big break this year, with their single This Year. They began to have some minor airplay on some folk-rock radio stations. The Sunset Tree was a concept album - a story about Darnielle's abusive stepfather. It is considered on of the most melancholy Mountain Goats albums: particuarly the song Song For Dennis Brown.

The Mountain Goats also have the tradition of continuity in their music, even throught albums. They have a series af songs that begin with alpha, which is a continuing story of a couple. They also have songs that start with Going to..., which describe the moods of certain places.