Let's assume that the Alcubierre drive has been created, and there are no problems with it, such as energy requirements or time dilation. The human species is united in a planetary government. Crossing the milky way galaxy takes about four months, and the cost of this is equivalent to about 10,000 USD, making tickets on cross galaxy passenger ships relatively cheap.

Thousands of habitable planets are available, but colonies may also be entirely space based. Instantaneous communication to anywhere in the galaxy is also possible. Creation of an average factory or other building is about six months. Terra-forming and cloning are possible but too expensive to be efficient.

There may be some conflicts with other species or colonies that decide to become independent. However most planets would end up joining to protect them from non-allied independent civilizations.

How long would it take to fully establish a governing system, economy, alliances with any extraterrestrial species, and everything needed for a fully functioning galactic civilization akin to something like Star Wars. Could 800 years be plausible, or would it take longer?

The end result would be a unification of different planets, with a group of people at its head. Each planet would have its own government, with certain freedom to create laws and otherwise influence its planets inhabitants, however they would all answer to the central authority.

All one would need to travel in any public government space is an ID card with some embedded verification data, and everyone would use the same decentralized currency. How long might this take, factoring in build times for settlements, possible disputes, and other complications?

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    $\begingroup$ As long or short as your story requires. And specifics on how would it work are important. Specifics about why would it even be thought to be a good idea are even important. You know, we do not have Earth government yet, despite the fact that there are pretty good reason for us to have one. $\endgroup$
    – Mołot
    Commented Jan 26, 2018 at 23:11
  • $\begingroup$ @Molot, the fact that the details are not important is referring to this question, not the story itself. Of course the details are important, I just wanted to differentiate this question from others that already talk about galactic governments by emphasizing on the time it would take to form . Sorry for the confusion, I'll edit it right now. $\endgroup$ Commented Jan 26, 2018 at 23:20
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    $\begingroup$ Details of how it would work are crucial to determine time to establish it. If you want government that works more like European Union, protecting freedom of travel and trade but not much else, it can happen much faster than, let's say, centralized government based on Soviet Union. $\endgroup$
    – Mołot
    Commented Jan 26, 2018 at 23:27
  • $\begingroup$ True, I hadn't thought of that, I'll add it to the question. $\endgroup$ Commented Jan 26, 2018 at 23:36
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    $\begingroup$ How many planets ? What you define as a minimum seed size for a colony ? And note that, once some idiot sets pen to paper there is technically a government - people are irrelevant to governments. :-) How fast can a factory be built ? How fast can you genetically engineer plant species to live on alien planets ? How fast can you mine resources ? Lots of detail required to answer your question - too much. $\endgroup$ Commented Jan 27, 2018 at 0:30

2 Answers 2


Between 5,000 and 6,000 years, using a whole lot of assumptions

For comparison, the American colonies were 2 to 3 months away from their mother country in Europe, and the Indian colonies about 4 months away. Using this comparison, it took between 150 and 300 years for those colonies, respectively, to break away from their original nation and establish themselves as independent.

Depending on your interpretation of modern politics, it could be claimed that we are closer now (in 2018) than ever before to establishing One World GovernmentTM, and we're still several decades off. Again looking at the current time period as the end of the colonial era, it could be said that it has/will have taken between 500 and 600 years for the following cycle to occur:

  1. Home nation begins acts of colonization
  2. Colonies established
  3. Colonies develop/become self sufficient
  4. Colonies revolt/declare independence
  5. Colonies form economic/social/political alliances with original nation
  6. Home nation and colonies reunify into one nation

Using this as a model, we could assume that a similar time scale might apply for extra-solar colonies as well, assuming that the travel and economic separation is similar, as you described it is. However, there is one key difference: colonies on Earth are/were limited in that a) there is a finite amount of space to go around and b) colonies very rarely, if ever, began establishing colonies of their own.

So while this 500-600 year cycle holds accurate for Earth, where colonizable area is finite, in the vastness of space with thousands, hundreds of thousands, potentially millions of planets to colonize, the cycle cannot be this fast. So instead, lets assume that the 500-600 year cycle refers to one "round" of colonization, and as a cycle completes the now-former colonies will begin colonizing anew of their own accord.

Modern estimates using the Drake Equation put the number of life-supporting planets in the Milky Way at around 15.6 Million. Let's just discount for the moment the possibility of terraforming, or colonizing non-life-supporting planets.

Assuming that each planet establishes an average 5 colonies per colonization cycle, and using the exponential growth formula, this means that all 15.6 million planets are colonized with 10 cycles, or 5,000 to 6,000 years.

All in all, it will depend on how your civilization works. If it is plagued by wars, it will take longer. If it is unified behind a progressive religion it might take shorter. However, assuming a social, economic, and political climate not that dissimilar to modern industrialism, this estimate may be accurate.

Two related references:

From Elite: Dangerous:

The galaxy's total NPC system population is approximately 6,632,313,733,791 NPCs on January 12, 3303.

The Core Systems also known as The Bubble is a sphere of about 150 light years around Sol with 19 thousand inhabited systems where powers compete for influence, resources, territory and control. The territory volume is about 13.8 million cubic light years, and encompasses over 20,000 inhabited systems with over 66,000 stations, starports and outposts.

Set about 1,300 years in the future, humanity encompasses a very small portion of the Milky Way

From Foundation by Isaac Asimov:

"(theatrically) Do you realize, Dr. Seldon, that you are speaking of an Empire that has stood for twelve thousand years, through all the vicissitudes of the generations, and which has behind it the good wishes and love of a quadrillion human beings?"

Set 12,000 years after any recognizable time, the Galactic Empire of Asimov's Foundation occupies the entire Milky Way, and has done so for so long that its scientists have forgotten what planet Humanity originated on


Honestly, depending on the circumstances, 800 years might be too long in my opinion. Since your system is extremly benefical for its members, while not having any real downsides (as far as I can see), most planets would join rather quickly in order to improve their economy, gain protection and so on. The time it takes to establish such a federation that spans significant parts of the galaxy would depend mostly on the history and culture of its members, I believe. For example:

  • Two races (or more) that have been at war for ages would refuse to join if the other joins.
  • Xenophobic races would refuse for obvious reasons.
  • Militaristc races might see such a federation as more limiting than benefical in their conquests.

What I'm trying to say is: If most galactic civilizations had no reason to be against this alliance, it would come in a matter of a few decades.

But thats only the alliance. The centralized government would take longer, again depending on the circumstances. I see 3 possible scenarios:

  1. The Imperialistic government: An empire conquers significant parts of the galaxy and decides to let the conquered planets be ruled by governors that these planets choose themselves, because ruling them themselves would be too much work.

Estimated duration till establishment of galactic supremacy: Depending on how sucessful they can conquer, 500 years, maybe more.

  1. External threat: An external threat makes the need for a centralized government obvious, for example an invasion by extragalactic beings that at first is unstoppable till alliance members unify under a common governing body.

In this case it all depends on the external threat, but the establishment of the first government could happen in a few months, after that maybe 100 years in order to grow to accept it.

  1. Peaceful process: People just grow together in a loose alliance and over time forge stronger bonds between members. After centuries of cultural exchange they elect their first central government.

Honestly, 800 years would most likely not enough for that to happen.

To sum it up: If people have a reason to create such a government, it will happen very fast, since the technological necessities are established.


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