Mars terraforming project was launched on the very same year, actually on the very same day, as Venus terraforming project. Unlike Venus, terraforming fleet did not experience major technical failures in the beginning and full terrafomation was completed far before year of 4112 (Which was when full Venus terrafomation was completed.)
However, Mars experienced major failures in establishing proper eco systems. End result of Mars terraforming was a desert planet, a deep red desert planet. Only few kinds of plants ever grew on Mars, and in very small numbers. One of them was the dandelion which became the national flower of the planet.
Population of Mars, by 9599, was half a billion (500 millions). Its population is among the lowest in Sol system. Living condition on Mars was harsh due to immense and constant sand storms as well as hot weather with nearly zero humidity. Water supply had never been an issue however.
Mars was governed by the Dietrich family after its independence since 9599. There was only one city on the planet, Kamtaka. This large underground city was home of 499 million people. The city featured a unique defense system by having a floating island above the city. A castle was built on this floating island. The Dietrich family lived in the castle until the end.
Year of 9999 was the end of the Dietrich family as an unknown phenomenon struck the castle, killing the last remaining members of the Dietrich. However, Mars still remained independent led by Eran Gro and Grace F.G. (Grace Flag Gro) and maintained a fragile alliance with weakening Venus.
2. Climate & Gravity
On Mars, average temperature was 32 Celsius all year around. Out of 365 days, roughly 363 days were stormy which created what Martians call “Burning festival” on clear days.
Interestingly, even during night time, average temperature remained identical because the sand would release heat back.
Martian air had 0 ~ 5% humidity and a lot of fine sand particles which were not ideal for human breathing for prolonged period. Therefore, it was recommended to wear breathing masks when one had to venture out for more than a day.
Martian gravity was 0.6. The original 0.4 gravity had been enhanced during terraforming phase by adding mass.
3. Miner's haven
Mars was very rich with minerals, iron, copper, gold, silver, aluminum, and an unknown material found commonly all over the planet. This unknown material had been considered as junk until early 9xxx. This unknown material became the most valuable material in the whole space afterwards.
This "junk" material had been renamed by Dr. Cezary A.C.M. : Abnormal chemical material. Using its special properties, Cezary was able invent to a new class of generator which generated enough powers to supply any class of warships and a new shielding technology. (Far later, it was renamed 'Modular shielding' when "Force shield' was invented.)
Over 95% of population on Mars was miners.
Mars was home to miners, and miners generally belonged to the Miner's guild, and the guild was run by a clan, namely the Dietrich and later the Gro.
4. Miner's dispute
Humans have had tendency of looking down on labor workers since they consider them as "low-end" workers in comparison to white collar workers.
Such a tendency started to cause conflicts with miners on Mars with others. This conflict was never serious enough to warrant wars. However, as the Dietrich started to rule the planet and founded the Miner's guild, this dispute became more and more serious and profund. The Dietrich was never favored by United Sol and was never given any political powers. Meanwhile the Bau and the O'ren gained so much political powers.
Eventually, on 9599, the Dietrich revolted and declared Mars independent.
The Dietrich family had been the dominant force on Mars for many generations until year of 9999. The Dietrich declared Mars independent from United Sol shortly before Venus declared independence. Independence of Venus hurt only ego of United Sol. However, Independence of Mars hurt United Sol financially because of nature of Mars.
Earth had long depleted its mineral deposits and had been relying on other planets for resources. Mars was their prime source since Mars was the closest to Earth. This had forced United Sol to obtain sources from further places with more risk and money involved in transporting resources.
Upon declaring independence, Kan Dietrich captured the only governing building on Mars in Kamtaka and captured all officers inside. He made a quick demand to United Sol to release Masu from a prison on Earth and send him back to Mars in exchange of sparing lives of the officers.
This demand was accepted (The decision maker at this time was Cecil Klisis.) and Masu was released and sent to Mars.
Ever since its independence, Mars had a close tie with Venus. They kept an alliance ever since 9599.
This revolt event is covered in [Shattered union arc]  [Revolts] .
6. The Dietrich family
The Dietrich family was miners based on Mars. They were NOT the first settlers of Mars however. Their golden era was when Gawain Klisis (Grandfather of Cecil Klisis) was the president of United Sol. Ever since, the Dietrich family had been in decline.
The Dietrich had been closely connected with the Nebula pirates. The Nebula pirates needed minerals from Mars. Mars needed allies. In charge of exporting ores and minerals, 3Ra Syndicate sent pirates to Mars, protecting them if needed. Otherwise, they’d do what pirates would do but never harassed Marian merchants and transports.
By 9599, the only remaining members of the Dietrich were two, the headman, Kan Dietrich, and his (clone) daughter Roon Dietrich. Kan was a fine leader and ruled the planet quite fairly. He was also supported by Masu the sage.
Kan and Roon both were murdered by Cecil Klisis on 9999, ending the bloodline forever.
7. Masu the sage
*Masu has his own arc: Masu arc.
Masu (8607 - 9699) the sage was one of the most powerful ESPs of the era. He was literally the living symbol of Mars as well as the Dietrich. His divine aura made everyone bow before him. Until his death, he served the Dietrich and was literally the leader of Mars. Even Kan Dietrich, the actual leader of Mars, never objected him, not even once.
Masu was also a close friend of Dr. Cezary, Marat, and Cecil Klisis. Those four people worked together in Project Marat.
8. The black knight
After Masu's death, Mars was weakened greatly. Mars had been experiencing lack of generals and officers ever since its independence. Masu filled this gap, but with his death, a huge gap was created. This gap was never fully patched. However, a general whom later bore a nickname, the Black Knight, filled some of this gap.
The Black Knight, his name was Eran Gro. The Gro was a vassal family (Clan) of the Bau. His reasoning for joining Mars instead of United Sol was because he admired Masu.
With Ssilen (The leader of the Gypsies), he forged "The Hellfire blade" (Pure black energy blade) which became his signature weapon.
He was one of the best swordsmen in clusters and was a fine general. It was safe to say that he was the one who supported Mars alone after The Dietrich fell on 9999.
Eran Gro was a very close friend of the White Knight, Juun, who was an agent of Andromeda union. Juun and Eran Gro, when they fought together, defeated Cecil Klisis in a pure swordsmanship play. However, they were forced to flee when Cecil decided to use his ESP powers.
After the fall of the Dietrich, Eran Gro took over the planet and convinced the Gro clan which had relocated to Venus after the fall of United Sol to relocate once again to Mars. Eran Gro eventually became the headman of the Gro shortly after.
9. Grace F.G.
Her maiden name was Grace F. (Grace Flag). She was the daughter of Jack Flag, a leader of local pirates found by Mars.
After Eran Gro cleared out the pirate gangs on 9701, Grace F. joined him. Few decades later, she became Grace F.G. (Grace Flag Gro). She always stated that she never liked her illegal last name, Flag, but never chose to remove it and always announced that she was “Grace F.” and later “Grace F.G.”. She had a habit of declaring her name in full but using only initials for her last names.
Ever since pairing up with Eran Gro, she fully supported him until the end.
Mars had little need and demand for public transportation. Bus was available on ground, but only very few utilized this transportation.
Since Kamtaka was an underground city for most part, subway was the dominant transportation. General view of Mars' transportation system resembled ours of 21st century except that it was under ground and that it went down to even one hundred meters below.
Since majority of population was professional miners, they had their own shuttles which left little need for any other transportation methods.
Life of a Martian is portrayed well in [Repairman arc]  .
11. Governing structure
Mars bore a form of dictatorship. There was no election since Kan Dietrich was the sole leader of the Miner's guild. New officers / members were chosen from interviews rather than elections.
However, when it came to matters related to mining, miners had a right to vote and object decisions made by the Dietrich family.
Unlike Venus, Mars experienced severe lack of men power in their government. The only fleet generals were Kan and Tryon until Eran Gro joined. The only high ranking officers were Masu and Roon until few new faces joined. Mars had always experienced lack of men power in both military and political areas.
The governing structure of Mars was very simple. Masu was the decision maker and was also the one who came up with ideas. After Masu's death, Roon took over most of domestic tasks while Eran Gro took over navy tasks.
Masu once said to Cecil, "We don't have the men power to write new laws. Therefore, I shall copy yours."
Mars copied Venus' laws, the civil laws. Later, Roon and Eran Gro added few more lines but overall Mars laws remained virtually identical as Venus'.
13. Roon Dietrich
Masu was the divine symbol of Mars and was also the father figure for Mars.
Roon was the holy mother symbol of Mars.
She was a rare ESP of both active and passive. Her passive power was her voice which soothed those in need. Her voice was told to be very nice. Some even described her voice as "The voice of a holy mother". She had a long brown straight hair tied like a long pony tail which reached her waist. Her overall appearance resembled that of an innocent girl. Her ESP class was A, specialized in mind reading. She was never able to read Eran Gro’s mind however due to him having the perfect mind.
She was Kan Dietrich's clone with a different gender. Dr. Anna claimed to have engineered her. However, the truth was that it was Dr. Cezary who engineered her. What was more: Roon was based on Marat's DNA template.
She was killed by Cecil Klisis on 9999.
How Roon was “constructed” is covered in [Masu arc]  [Dr Anna] .
Mars was bombarded and went supernova on 12328.
Prior its destruction, the Gro clan had fully dominated the planet.