Ling and Bak are the Chief Magistrates who headed the State of Gaoling until 174 AG, when they became candidates in the democratic elections for Gaoling's governorship. Capable bureaucrats, they represented the old order of the Earth Kingdom.
Ling and Bak belonged to the old Earth Kingdom bureaucracy, and were described by Mayor Rhee as "two of Gaoling's finest government officials". After Earth King Wu descided to dissove the Earth Kingdom in favor of independent states with democratically elected governments, Ling and Bak opted to enter the upcoming elections in the State of Gaoling as candidates for the governorship. They enjoyed the full support of Rhee who believed that either would be an ideal head of government.
When King Wu travelled to Gaoling with Team Avatar, he was greeted at the local airport by Ling, Bak, and Rhee. The group then went to Gaoling's City Hall, where Avatar Korra and the King were formally introduced to the two bureaucrats and informed about Ling and Bak's candidacy.