Assertion

Assertion is a resilient and deeply honest band formed in the Pacific Northwest by drummer/vocalist William Goldsmith (known for his work with Sunny Day Real Estate and Foo Fighters) and guitarist/vocalist Justin Tamminga. The band emerged out of a shared need to create music with genuine expression rather than obligation, releasing their debut album *Intermission* in 2021 to critical acclaim for its raw, earnest energy and 90s-inspired sound. Their music blends alternative rock with post-rock influences, anchored by dynamic guitars and a powerful rhythm section.

After *Intermission*, Assertion spent years writing and recording through difficult personal challenges, including lockdowns and a traumatic brain injury to Tamminga. This period of upheaval fueled their sophomore album *Basking In The Gaslight*, released in July 2025 through Spartan Records. The album is a cathartic, emotionally heavy document of survival, resilience, and healing, confronting themes like psychological manipulation and trauma without losing a sense of hope. Produced by Tamminga, *Basking In The Gaslight* continues Assertion’s blend of alternative and post-rock, driven by unfiltered emotion and a restless desire to grow.

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