The Park Service of the State of Humanity, sometimes called National Park Service or Park Rangers, was a law enforcement institution. It was associated with the Ministry of Land, the Bureau of Police, and the Armed Forces Commission.

A nature reserve existed in the northeastern Baovuldian deep fjords and mountains since Union times. The area was relatively sparsely settled, and the national police had maintained a dedicated team to patrol the region against poachers and other illegal use. This unit called itself the Fells Ranger Department. It largely remained as is when the Union became the State, though it now relied on the Ministry of Land for financing, which considered the region a "valuable wildlife area". The ministry also financed or created new institutions in other protected areas, essentially making sure that all wilderness regions not already managed by a member state or another institution was covered.

Following sweeping accords to protect wildlife areas on Bao-Mou closed with the Dwarven Empire, the ministry decided to make the rangers' domain into the Baovuldian Fells National Park, an area enjoying considerable protections from human use (which was essentially restricted to on-path tourism). A year later, in 426, the Park Service was formally founded to maintain and protect the national park; this was the job of the Rangers.

The Park Service was vested with some police authority, including the right to wield lethal arms in the name of the law, and its new recruits went through the same cadet training as professional military officers and national policemen. It counted only a few hundred enforcers and nature experts among its ranks at first.

The other large national wildlife region of the Litchian desert was added to the Park Service's portfolio in 428. The area was formerly patrolled by local forces, but was now also designated a park. There were fewer restrictions on use here, but since the region was mostly empty desert, the rangers' role was largely patrolling the border and checking illegal traffic. The rangers acquired a first reconnaissance helicopter in that year, and also purchased three water-bomber firefighting planes from Tokken in 433. They patrolled the desert mostly in light all-terrain cars, and squad cars for the national park.

Many Tokken islands were only sparsely inhabited, featuring perhaps a port and oil terminal on an otherwise barren, lightly forested island. Most of this wild space (which had regenerated quite well from the tears of war) was designated a National Wildlife Area in 432 and put under the Park Service's management, again mostly to patrol against use and also for firefighting.

The Park Service had a kind of countryside police role from the beginning, and found itself sharing border patrol responsibilities with the Ministry of Economy's Customs Bureau.

The Service was joined to the new Armed Forces Commission in 440, alongside the Maritime Customs Fleet and other military-like institutions (though not police forces). Its militaristic character strengthened somewhat over time as a result of this. Many of the Service's closest bodies, like the National Police and the rest of the Customs Bureau, were however not part of this merged administrative structure. Thus the rangers found themselves with military-issue patrol cars rather than the civilian police equivalent, and it flew assault helicopters along the borders.

The Service was disbanded in 456 as a result of the creation of the Border Gendarmerie Commission, which made use of National Police, Customs Bureau officials, and soldiers to patrol borders. Most rangers were adopted into the new Mounted Border Gendarmes, whereas catastrophe response capabilities were mostly transferred to the Federal Air Force and the Northern Fleet.