The Bajoran Militia was a Bajoran military organization dedicated to the protection of Bajor and its territories. The Bajoran Provisional Government authorized this organization, comprised of mainly former Bajoran Resistance fighters.
The rank structure bore resemblance to many Earth armies. Like in Starfleet and Earth armies, officers usually graduate from an academy. In this case, graduates came from the Bajoran Military Academy. (DS9: "Emissary", "Meridian")
The Federation Starfleet agreed to work with the Bajoran Militia to run the abandoned Cardassian space station Deep Space 9 (formerly known as Terok Nor), first in orbit of Bajor and later near the Bajoran wormhole. Captain Benjamin Sisko, from Earth, was DS9's commanding officer from 2369 to 2375, with Bajoran Militia Major Kira Nerys acting as first officer during that time. When Sisko disappeared in 2375, Kira took command. (DS9: "Emissary", "What You Leave Behind")
For a time the Militia operated a small space fleet dubbed Space Arm that included at least one Breen-built Chok Thol-class frigate. However, politics in the Chamber of Ministers in the late 2390s included moves by the Conservative Association to shut down Space Arm on grounds of cost and lesser effectiveness compared to Starfleet; these were opposed by the Bajoran Nationalist Party. An economic recession at the turn of the 25th century led to the Socialists joining with the Conservatives to defeat the Nationalists on budgetary grounds, and Space Arm was decommissioned effective June 2401. Its personnel either retired, transferred to other specialties, or joined Starfleet. (Bait and Switch: "From Bajor to the Black, Part I")