Shi Yomi has become the 23rd district of Arunachal Pradesh.It was inaugurated by Pema Khandu (Arunachal Pradesh Chief Minister) in presence of Union Minister of State for Home Kiren Rijiju. It was created by bifurcating West Siang district with its headquarters at Tato. It will have four administrative units namely Mechuka, Tato, Pidi and Manigong. Two more districts Pakke-Kesang and Lepa Rada will be formally inaugurated in the state within taking the total to 25.

In August 2018, Arunachal Pradesh Legislative assembly has passed Arunachal Pradesh Re-Organisation of Districts (Amendment) Bill, 2018 for the creation of three new districts.