The idea of Swallow the Sun was formed in spring 2000 by Juha Raivio. He had few songs that didn't fit the style of his band at the time, Plutonium Orange. Pasi Pasanen was playing drums in Plutonium Orange at the time, so Juha started rehearsing the songs with him. In 2001 they started to look for people to play with - the first one to join the line-up was Markus Jämsen, whom Pasanen and Raivio already knew from their earlier projects. After Jämsen, along came Mikko Kotamäki from Funeris Nocturnum as the bassist/vocalist. Later on they decided that the band needed keyboards and a dedicated bassist, so they turned to Funeris Nocturnum, from where they got Aleksi Munter on keyboards and Matti Honkonen on bass, and the line-up was complete.

The recordings of the 4-song demo 'Out of This Gloomy Light' took place in January 2003 at Sam's Workshop, and resulted soon in a record deal with Firebox Records. The recordings of their first full-length album started in late July 2003 at the same studio the demo was recorded, and it was released in November. It immediately got huge press in Finland and loads of appraising reviews. Swallow the Sun was selected as the Newcomer of the Year 2003 in Inferno-magazine's (the 2nd biggest music magazine in Finland) poll, and was third in the same series in Finnish Metal Awards 2003. Kerrang! called Swallow the Sun "One of doom metals finest moments to date" and gave the album 5/5 K's.

After the release of the album Swallow the Sun got a deal with Welldone, the Finnish representative of Clear Channel Entertainment Company, and started a year of intensive gigging. They played in lots of festivals in Finland, including Tuska Open Air Metal Fest and Provinssirock. In the end of the year Century Media/Olympic Records released 'The Morning Never Came' in USA, and it has got rave reviews in all the major metal magazines.

In February 2005 Swallow the Sun entered Sam's Workshop again to record their 2nd album 'Ghosts of Loss'. A single 'Forgive Her...' was released in April 2005, and it hit the official Finnish Top 20 Singles chart at position 4 on it's first week. It stayed on the charts for 6 weeks and was the first Finnish doom metal release ever to enter the charts in Finland.