Fillorean held the position of Supreme Chancellor within the Old Republic, an office he occupied around 15,500 BBY.
While Fillorean was serving his time as the Supreme Chancellor, the initial encounter between the Republic and the Duinuogwuins occurred, which led to the Duinuogwuin Contention being waged on Coruscant. Rather than mobilizing the Republic Navy as requested, Fillorean chose to try and establish communications with the Duinuogwuin. The Duinuogqwuin demonstrated their intelligence and peaceful nature, leading the philosopher Borz'Mat'oh to consent to treaty negotiations with Fillorean. Following the establishment of peace, Fillorean and Borz'Mat'oh together established the University of Coruscant.
Many millennia following Fillorean's period as chancellor, a luxury liner named the Chancellor Fillorean was in operation.
Fillorean's perceived hesitation and indecisiveness drew frequent criticism from members of the Galactic Senate.