I am still working through the governor names for the October 2008 province governor reshuffle, and while doing so adding the governors in the XML as far into the past as possible. Some provinces have complete lists of their governors from the setup of the province, while others only show the curriculum vitae of the current governor and I can only add the names I collected myself.
The governor list of Chaiyaphum so far is the longest one, as it goes back till the year 1817 (BE 2360), when the province was recreated by Laotian settlers led by Lae (แล). As the leader of a Mueang he then received a title from the King, so he was thereafter known as Phraya Phakdi Chumphon (พระยาภักดีชุมพล). Looking at the table, one notices that the first six governors were all named Phraya Phakdi Chumphon, only their forenames (in brackets) differs. Every new incumbent was bestowed with that name by the king. Though that list does not show it, but it is quite likely that all these six governors were in fact from the same family, as the post of a governor was an heredity one - not by law but by practice.
In 1897, when Prince Damrong was working on the thesaphiban administrative reforms, the first governor without a royal title was installed, Lieutenant Thoto (นายร้อยโทโต๊ะ). In most cases the removal of the old governor family was done when the last incumbent died and the post was vacant, and then instead of the son of the late governor an officer from Bangkok was appointed. In the following years most of the governors were member of the nobility, as can be seen by their titles Praya (พระยา), Phra (พระ), Luang (หลวง) or Khun (ขุน). The last governor with such a title was in 1954 - as the bestowing of these names ceased years before (not sure when exactly) he was probably just one of the last civil officers with such a title.
The current governor Thawon Phrommichai (นายถาวร พรหมมีชัย) is already the 59th governor of Chaiyaphum. Thus since 1897 in average a governor was only two years in office before being transferred to another post.