Open Historia

Cities and Structures

Cities on the map and the bases, ports and landmarks that get built during a campaign.

Two kinds of thing are drawn on top of the political map: cities, which come with the world, and structures, which get built during a campaign.

Cities

Cities come from the scenario. Modern Day carries its own list of about 2,500 cities. A scenario on the stock world map uses a stock set of roughly seventy thousand; a custom scenario can ship its own, or import from the same database. A scenario with no cities shows none.

The stock cities appear from about zoom 3.4, the biggest first, and get denser as you zoom in. A scenario's own cities show by their tier: capitals first, towns only when you are close in. Click one for its name, population, whether it is a capital, and its tier.

On beta a city's card leads on. It names the region the city stands in, and clicking that name opens the region's card.

Cities change

The world can rename a city and change its population, and it does both for real reasons:

Renaming happens when a city is renamed after a leader or an ideology, when a capital is re-designated, or when a conqueror gives a captured city their own name. It works on any city on the map, including ones that shipped with the world rather than being authored by a scenario.

Population moves when something plausibly moves it — a siege, a famine, an epidemic, a bombing or an evacuation shrinking a city; an industrial boom, a resettlement programme or a refugee influx growing one. The world always writes the new total, not the change.

That means a long campaign leaves a visible demographic trace on the map, which is one of the quieter pleasures of playing one.

On beta, cities follow their country, and can change by the year. When a country's population moves — its statistics are brought up to date, or a war costs it men — its cities move by the same share, once the change comes to half a per cent or more. A city an event has just changed keeps what the event says that turn, and follows its country from there, so a city bombed flat starts again from what was left. A scenario can also give a city its population by year (in the map editor's city card, Population by year), and the map reads the figure for the game's year, between the two years around it, until the world or the Game Master sets one of its own.

Structures

Structures are markers placed during play: military bases, ports, embassies, airfields, research facilities, landmarks — the kind is free-form, so the world names whatever it needs.

Each has a name, a kind, an owner, a position, a status — planned, under construction, active, damaged, inactive, abandoned or destroyed — and optionally a note and a founding date. The game places a new structure by the place its event names and keeps it off other markers.

Structures never move borders

This is the rule worth knowing. A structure's owner is whoever runs the facility, not who owns the ground it stands on.

An American airbase in Germany does not make that region American. An embassy is not a piece of the sending country. Building a port in an allied country annexes nothing.

If you want the ground, that is a territorial change, and it has to happen as one.

Building and losing them

Structures appear when an event founds or constructs one, change status as events damage, abandon or destroy them, and are taken off the map when one ceases to exist. Building something under the name of a structure that already exists — or a name it once had — does not add a second one: the existing one stays. A structure that is renamed keeps its old name as an alias, so later events can still find it.

You get structures by ordering them — "begin construction of a naval base at Gdynia" — and by the world building its own. Watching foreign bases appear near your borders is a genuinely useful early-warning system.

On beta, what an event builds is put on the map. The checks after each time skip read its events for what was built — bases, shipyards, data centres, ground stations — and put up to five new structures a turn on the map. A structure whose place is not on the map is placed in its country, near a place the map does have, and its card says so; on your own structures, and your puppets', Accept keeps that place and Move lets you put it where it belongs. One credited to a country with no land goes to whoever holds the ground. A structure's card also lists the latest events that built or changed it, the names it had before, and the region it stands in. Structures are drawn half again as large.

Placing them yourself

The cheats panel has map-feature tools: edit an existing city or structure, add a new one, or clear out ones that have accumulated and stopped mattering.

In a scenario with its own city list, a city you add joins that list, with its population and tier. The stock world cities cannot be changed in play, so in a scenario that uses them a new city is placed as a map marker instead, without a population or tier. Clear Map Features can also switch a scenario from its own cities back to the standard world list.

For authoring a whole world's cities, use the map editor, which can import from the full city database or place them by hand.

Next

Open Historia is under active development on two channels, and this wiki is written by hand — a page can fall behind a release. Last checked against the game on 2026-10-25 · main 6e6239c4 · beta d7e8fa85. If something here does not match what you see in the game, trust the game and say so on Discord.