Claassen was born in Heerlen's Zuyderland Hospital on 13 July 1971. His father was a member of the Labour Party and a senior union leader of Abvakabo.[1] Claassen was raised Catholic, but he has said that he was "cured of Roman Catholicism" after visiting Vatican City at age seventeen, concluding it was a charade.[2] Claassen completed his nursing training in the late 1980s, and he worked as a hospital nurse for over twenty years, successively in a pediatric ward and an intensive care unit. He was employed by the Zuyderland Hospital for most of that period.[1] He switched careers in 2008 and became a healthcare educator and manager at the Zuyd University of Applied Sciences. He also completed a master's degree in applied science at Maastricht University.[1][3][4]
Political career
In a 2024 interview, Claassen described that he was inspired by the rise of right-wing politician Pim Fortuyn. Poverty was rising in Heerlen as a result of the closure of coal mines in the region, and Claassen believe those issues could only be solved by the political right.[1] He was elected to the Provincial Council of Limburg in March 2019 and to the municipal council of Landgraaf in March 2022. He stepped down from both positions in December 2023.[3]