Fellowes was the son and heir of Newton Fellowes, the veteran Whig MP for Andover, 1802-20, and Devon North, 1832-37, who had wrestled the succession to the earldom of Portsmouth from his older brother by having him declared insane and his marriage annulled in 1823, disinheriting any putative heirs.
Fellowes, who seems to have been plagued by poor health, remained a lax and silent attender in his final parliament.
At the 1835 general election Fellowes quietly retired from Andover, where the local Tories were determined to recapture one of the seats.
Fellowes, who is conspicuously absent from a twentieth-century history of his family, died unmarried and intestate at Eggesford in February 1847, ‘after a long and lingering illness’.
