[1] The seat became vacant after the uncontested election of incumbent Mohamad Hasan of the United Malays National Organisation (UMNO), a component of Barisan Nasional (BN) coalition was declared null and void.

[2][3] In the 2018 elections, Mohamad Hasan, the 3-term former Menteri Besar of Negeri Sembilan won the seat uncontested after People's Justice Party (PKR)’s candidate Dr Streram Sinnansamy was not allowed to enter the Nomination Centre to file his papers.

[5] A fresh election was called to be held after Mohamad Hasan's appeal was dismissed by the Federal Court on 18 February 2019.

[10] Meanwhile, Dr S. Streram, an anaesthetist who is the Rembau PKR deputy chief, said he would leave the candidacy to the party leadership and vowed not to contest as an independent if he was not selected as candidate for the Rantau by-election.

Mohamad's past speeches which purportedly touch on vernacular schools and remarks describing non-Malays were which alleged to be racists and has sparked outrage among the public.

[18] Mohd Nor Yassin was also the Pan-Malaysian Islamic Party (PAS) candidate for the state constituency of Gemencheh during the 2013 general election.

[19] Former Malacca Chief Minister, Idris Haron promised in a campaign speech that if BN won the by-election, they will provide two goats for a feast.

[22] A case involving an RM10 million being remitted and transferred through a money changer by Mohamad to buy a luxury apartment in London has been brought up by the Speaker of the Negeri Sembilan State Legislative Assembly.