Run a country.
Watch the economy answer.
Sovereign is a free geopolitical strategy game that runs entirely in your browser. Take any of 204 countries, set its taxes, welfare, industrial and monetary policy, and watch a month-by-month simulation respond — through growth, inflation, unemployment, elections and the patience of the public.
Runs in any modern browser · No account, no install, no tracking · Works offline once loaded · Saves stay on your device
What you actually control
Sovereign is a sandbox, not a campaign. There is no victory screen — you decide whether you are chasing prosperity, equality, liberty, influence, or a balance of your own.
Fiscal policy
Income-tax brackets or a flat rate, corporate and land taxes, health and education, social protection, infrastructure, defence, housing, childcare and pensions — each with a visible budget cost and a lag before it bites.
The central bank
Set an inflation target and decide how independent the bank is. It runs its own reaction function; the more independence you grant, the less you control the rate and the faster expectations anchor.
Cities
Every country has real named cities. Fund local policing, prevention, services and maintenance, watch a crime-pressure index respond, and queue hospitals, metros, universities and freight terminals.
Trade
Sign five-year commodity contracts in food, energy, manufactures and technology. Deliveries are capped by real production capacity, tariffs become customs revenue, and sanctions or war suspend the route.
Politics
Eight parties, a hundred seats, coalitions and elections. Reforms cost political capital, unpopular ones cost approval, and a governing coalition has to be held together.
Diplomacy & defence
Embassies, research and climate pacts, non-aggression and defence treaties, sanctions. Split a defence budget across army, navy and air forces, and choose a doctrine.
War on the border
Declare war on a neighbour and a front opens along the land border the two countries actually share — computed from the map, so China and Russia have fourteen neighbours each and Germany nine. The line moves each month with the fighting, and you watch it shift on the map.
Named objectives
Aim an offensive at a city. Every one has a depth — how far past the border the front must reach before it falls. Buenos Aires sits 41% in, Salta 90%. Taking a city costs the defender the output and the confidence that went with it. Borders never move.
The simulation is a real model, not a slider that goes up
Output is produced, not granted. Every month the game solves a small macroeconomic model for all 204 countries.
Supply — what the country can produce
A Cobb-Douglas production function, Y = A · K0.33 · L0.67. Investment builds a capital stock net of depreciation. Productivity grows with research, competition, openness and administrative quality — and catches up toward the frontier only where institutions, schooling and trade support it, so weak states converge slowly or not at all.
Demand — what it actually produces
An output gap driven by real interest rates against a modelled neutral rate, the fiscal impulse, competitiveness, trade and shocks. Demand moves output around the supply path. It cannot raise it for long — stimulus buys a boom and pays for it in inflation.
Money — the price level
A Taylor-type policy rule, a modelled neutral rate, a central-bank balance sheet and a credibility score. Inflation follows an expectations-augmented Phillips curve. A credible bank disinflates cheaply; a bank that keeps missing its target does not.
People — the labour market
Unemployment follows Okun's law around a structural floor set by labour rules, minimum wages, training and placement programmes. Participation responds to the pension age and childcare. Population changes through modelled fertility, ageing and migration.
An honest note on realism. These are recognisable textbook relationships, simplified to one line each and tuned for playability. Nothing here is estimated from data or calibrated to any real country, and no number the game shows — a growth rate, a crime index, a city budget — is a statistic about a real place. It is a game that argues with you in the language of economics, not a forecasting model.
Three difficulty modes, and nothing hidden
A mode is a bundle of sandbox rules you can see and edit. Switching modes never restarts your world or rewrites your policies.
| Rule | Easy | Medium | Hard |
|---|---|---|---|
| National debt | Switched off entirely | Forgiving carrying costs | Standard carrying costs |
| Supply shocks | None | Every 5 months | Every 3 months, 50% harsher |
| Political capital | Rebuilds 50% faster | Normal | 30% slower |
| Reform cost | 30% cheaper | Normal | 35% dearer |
| Rival nations | Cooperative | Normal | They sanction each other, and you |
Play in 1970, 1985, 2000 or today
An era does not just change the date. It rebuilds the world with the states, prices, trade barriers and monetary arrangements of the period — and then history keeps happening around you.
The states of the period
Start in 1970 and the Soviet Union covers fifteen present-day countries as one state, alongside Yugoslavia and Czechoslovakia. Bangladesh, the UAE and Zimbabwe do not exist yet. Sri Lanka is Ceylon, Burkina Faso is Upper Volta, and the Soviet cities are Leningrad, Sverdlovsk and Alma-Ata.
Divided countries
Lead East Germany or West Germany, North or South Vietnam, North or South Yemen — each a separate country with its own map shape, cut along the border of the period. East Berlin, Leipzig and Dresden on one side; West Berlin, Hamburg and Munich on the other. Vietnam is divided at the 17th parallel. By 1985 Vietnam is whole again; by 2000 all three are.
The economics of the period
1970 runs on Bretton Woods pegs, high tariffs, heavy capital controls and central banks that answer to governments. By 2000 you get open trade, independent banks and explicit inflation targets. The productivity frontier moves with the era, so catching up in 1970 means catching up to 1970.
History happens while you play
Start in 1970 and the map changes on schedule: the Gulf states and Bangladesh in 1971, the Portuguese colonies in 1975, Vietnam reunified in 1976, Zimbabwe in 1980, Germany and Yemen in 1990, the Soviet Union in December 1991, Yugoslavia in 1992, Czechoslovakia in 1993, on to South Sudan in 2011. Play 1970 through to 1995 and the world goes from 152 states to 202.
A world with its own agenda
Rival nations fight their own wars, against neighbours they have fallen out with and clearly outmatch. Friction builds where two neighbours are governed very differently, or where one dwarfs the other — and agreements hold it off. On the hardest setting, roughly twenty-five wars break out between other countries in fifty years.
A scenario, not a historical atlas. Territory is approximated by grouping present-day borders, so the internal borders of the period are not drawn and partitioned states are left unified. No border or name here is a comment on any territorial dispute.
Easy removes sovereign borrowing completely: deficits are simply not financed by debt, so there is no interest, no debt ratio and no restructuring. Everything else still constrains you — taxes, programme costs, construction time, political capital and inflation.
Questions
Is it really free?
Yes. No price, no account, no advertising, no analytics and no tracking. Sovereign is one HTML file served as a static page.
Does it work offline?
Yes. Once the page has loaded, the entire simulation runs on your own machine. Nothing is sent anywhere. You can save the page to disk and open it later with no connection at all.
Where do my saved games go?
Into your own browser's storage, on your device. Browser storage is tied to the page address, so use Export save file in Sandbox if you want a portable backup or plan to play from a different location.
Does it run on a phone?
It does, and the layout adapts, but the interface has a lot of panels and is considerably more comfortable on a tablet or a laptop.
Are the country statistics real?
Starting conditions are rough, hand-set scenario values in the right order of magnitude, not current official statistics. City names are real places; the crime, budget and development figures attached to them are invented gameplay indices. The map's borders are a scenario simplification and are not a statement about sovereignty or recognition.
Can I play a country that isn't on the list?
Every UN member state, both observer states and nine further scenario entities are playable — 204 in total. Select any of them on the map and choose Play as.
Can you play as the Soviet Union?
Yes. Start in 1970 or 1985 and the Soviet Union is on the map as a single state covering fifteen present-day countries, with Moscow, Leningrad, Sverdlovsk and Alma-Ata among its cities. Yugoslavia and Czechoslovakia are there too, and 2000 has Serbia and Montenegro.
Can you play as East Germany?
Yes. In 1970 and 1985 Germany is divided into East and West, each a separate country with its own territory cut along the inner-German border. Vietnam and Yemen are divided in the same way. From 2000 onward all three are unified.
How accurate are the historical borders?
The dividing lines are hand-fitted from well-known geography, not surveyed boundary data, over map outlines that are themselves simplified. Each piece is checked against the historical land area when the game is built — West and East Germany come out within 4%, the two Vietnams within 3%. It is a playable scenario, not a historical atlas, and no border or name in it is a comment on any territorial dispute.
Does the map change while you play?
Yes. Starting from an earlier era, twenty-six historical events fire on their real dates: colonies gain independence, Vietnam and Germany and Yemen reunify, and the Soviet Union, Yugoslavia and Czechoslovakia dissolve into their successor states. A dissolving country hands its output, population and armed forces to the states that replace it. You can switch it off in Sandbox.
How does war work?
Declaring war on a country you share a land border with opens a front along that border, computed from the map itself. Each month the two armies fight for it and the line moves toward whichever is winning, drawn on the map as it shifts. Supply falls the further you push past your own border, so an offensive runs out of strength on its own. Against a country you do not border it is a limited war — attrition, no front. Borders never move and no country is ever annexed.
Can you attack a specific city?
Yes. In a land war you can aim the offensive at any of the defender's cities by name. Each has a depth — how far past the border the front must reach before it falls — with the largest cities sitting deepest and best defended. Taking one costs the defender the output and the public confidence that went with it.
Is there a way to play without a debt spiral?
Three ways. Easy mode removes national debt entirely, so deficits are simply not financed by borrowing. You can freeze the debt stock instead, which keeps what you carry without letting it grow and charges no interest. Or you can leave debt on and use the relief operations — refinancing and restructuring — as often as you can afford the political capital.