I agree 90% about your reply

The Martians would split up into atheists and agnostics and there’d be constant war between the sects.

@WilliamFleming Has there EVER been a historically recorded war between Atheists and Agnostics?
There have been innumerable wars fought between religious sects and differing religious belief systems though and the casualties and collateral damage counts have been enormously high.

@Triphid Innumerable? That would be too many to count. I can only think of a handful of such wars.

How would you control the future generations? Do you think young people would learn about and adopt religion or might create new religions in your Martian society?

@WilliamFleming It seems to me that you aren't quite researching enough into wars/conflicts either caused or based upon religions/religious differences here, since humans and their religious beliefs/difference have been warring over who's God/s, etc, are the only true one/s since religions were first invented.
As for the assumed Extraterrestrial Martian Colonists, then considering that it WOULD have been established sans Religion in the first place, then logically, would it NOT remain sans religion given, for example, that a society/group that is disease free will remain disease free UNLESS some disease is introduced by either covert/deliberate means from an external source?

@Triphid I was just going by memory, but here are some actual studies. You are right that it’s more than a “handful” but religion does not figure very prominently in the history of war.

My feeling, personal opinion only, is that some form of religion would arise spontaneously among the Martian population just as it arises on earth. The religious impulse is deeply imbedded in humanity.

Even if not, wouldn’t there be communication with earth? Wouldn’t religious ideas be discussed on forums? Would books be available?

Maybe a planet in a more distant solar system would be more suitable.

@WilliamFleming But those raised sans religion, i.e. Xstianity/Judaism/Islam, etc, would know already about the harm they have caused here on Earth and would, most likely, reject it outright.
Since to have travelled to Mars, logically, they would have been of a greater scientific mind with a great knowledge of the histories of the planet they were leaving behind and therefore determined NOT to repeat the mistakes of the past at any cost.

@Triphid I can see that the original settlers would be very zealous and fixed in their opinions but the children would have curiosity, and their minds would be open. They’d wonder where all this came from and what it means. They’d be full of awe and reverence, not for “God” but for the mystery and grandeur of nature and for the enigmas of conscious awareness and personal identity.

Looks like I neglected to give the link for those studies about religion and war.

[google.com]

This has prompted me to make a new post.

Sweden and Norway the weather can suck but from what I’ve learned they are so much more evolved then the backwoods crazies that inhabit the US and other religious countries!!! 85% non religious

@Triphid it is funny, i did not remember.hahaha

@Triphid, @WilliamFleming i have to reply your comment! I'm sorry, but I find it ridiculous that Martians can be converted to religion through Christian or Muslim evangelistic television channels.

@WilliamFleming What you see re-the original settlers as being zealotry and fixed mindedness is your own take on the matter.
Have not such traits also been the reason/s WHY religions exerted their somewhat 'iron grip' on mankind for so long PLUS in times gone by LITERALLY forced native peoples to become Christians, etc?
It IS still occurring today in a slightly different way with Islam and those insistent Door Knocking Christian Sects but the force applied by the Christian Sects has dissipated, thankfully, but in some cases it has been resurrected by the zealotry of the more radically driven Sects of Islam sadly.
Curiosity is a very good thing and should ALWAYS be encouraged under normal circumstance, especially with children and young people because it teaches them to think, research, examine, question and then to decide for themselves rather than merely follow the prevailing trend AND is that precisely how Humanity, Human Knowledge, Medical and Scientific Development has occurred and grown?
So Yes, the children of those Human Settlers in this theoretical Martian Colony might well begin to question BUT they will also listen, learn, discuss, examine, etc, and may well see the reasoning as to why their parents/predecessors rejected religions entirely in favour of creating a community based upon mutual cooperation, unity, social oneness rather than the divisiveness, etc, that is inherent in any social system with religions at its core.

@Triphid I remain pessimistic that your Martian colony would remain atheistic for long or that life under such a regime would be characterized by mutual cooperation, unity and social oneness, and I disagree with your assignment of divisiveness, etc. to religion.

You need not start a colony on Mars. You can look at the results of atheistic regimes over vast expanses of Earth. [en.m.wikipedia.org]

Atheism as a state ideology has never succeeded for long, and many of the regimes have been marked by authoritarianism and brutality. Please do not include me in the Mars venture. I’m getting along well with my religious neighbors and kin and have no grievances.

@WilliamFleming Atheism and disbelief in religion /Gods/Deities has been around for centuries, if not millennia, don't get it confused with the Authoritarianisms of Nazism, Communism and the like BECAUSE it IS not nor never has been such.
I ask you this in the HOPE that you WILL answer honestly, HAVE you ever had or heard of an Atheist or Atheists knocking on doors to sell or speak to you in YOUR home about Atheism?
Atheism promotes Free-Thought and Free-Thinking, Logic, Reasoning, Understanding, Individuality, Morality WITHOUT expectation of Reward and almost innumerable other thing good and beneficial to the world and the environment, etc.
Atheism as far as I can tell, after 50+ plus years as an Atheist, does NOT want to rule the World with an Iron Fist, it does NOT want to tell the world what to think and how to think, it does NOT and never has committed brutality upon anyone religious, though the same cannot be said for the religious when it comes down to their treatment of Atheists, etc, and history itself WILL bear me out on that FACT btw.

@Triphid I have never heard of an Atheist or Atheists knocking on doors to sell or speak to you in YOUR home about Atheism. I did however take an undergraduate course in the philosophy of religion, taught by an extremely zealous atheist. I learned absolutely nothing about the philosophy of religion. The entire semester was spent listening to his tirades. If anyone tried to question any of his pronouncements he would cut them off in mid-sentence with a stern rebuff. Not only was the course extremely irritating, it was a total waste of my father’s money. I feel angry right now just thinking about it almost sixty years later.

All of my education was in rural or small-town Alabama, and not ONCE was religion ever pushed or advocated by any of my teachers.

As I said earlier, religious people don’t bother me. I am not in accord with Christianity as presented by traditional churches, but I do not demonize anyone because of their religion. I know that religious organizations have sometimes been authoritarian and brutal, but I am not affected at this time and location.

So far as the question of the existence of God, no one alive knows or understands reality at that level and it is absolutely stupid to go on about it. Humans have no idea of the meaning of existence and we haven’t a clue as to what we ourselves are or as to the nature of conscious awareness. The only rational response to the overwhelming mystery of existence that I can see is that of abject bewilderment.

@WilliamFleming Sounds to me like that 'Atheist Teacher' was little more than a complete and utter arse-wipe, and that's being kind to say the least.

But without religion, how do we know who to hate and cast out?

Like OPrah..