The Trelawny family had extensive political interest in Cornwall. Trelawny entered Parliament at a by-election on 20 April 1713 as Member of Parliament for West Looe, a family seat, and was returned at the 1713 general election soon after.
The Trelawny family's political presence in Cornwall was substantial. Trelawny entered Parliament through a by-election on April 20, 1713, as MP for West Looe, a seat that was part of his family's influence, and was subsequently re-elected at the general election of 1713.