Formed in 2008 in Kharkiv, Ukraine, Sunchild is a progressive rock project led by composer, keyboardist, and vocalist Antony Kalugin. The project was established to explore vocal-driven, conceptual song structures, operating in direct contrast to Kalugin's other primary band, the heavily instrumental symphonic rock group  Karfagen. Kalugin also explores melodic progressive rock alongside UK musician Will Mackie in the project Hoggwash.

Operating as a project band, Sunchild utilizes a rotating cast of session musicians and classical players to execute its complex arrangements. The core rock instrumentation frequently features guitarist Max Velychko (who has a solo project called Inside The Sound) and drummer Sergii Balalaiev, both of whom have extensive performance histories within Karfagen and their own instrumental solo releases.

Sunchild's compositions are characterized by the integration of traditional progressive rock instrumentation with organic classical elements. Kalugin’s layered synthesizer and piano passages are routinely accompanied by oboe, bassoon, violin, cello, and the bayan (Eastern European button accordion). The project debuted in 2008 with the album The Gnomon and has consistently released sprawling, conceptual records that build upon the contemporary symphonic rock tradition through multi-part suites and elaborate melodic themes.