Arising after the American Liberal-Conservative Civil War (not to be confused with a myriad of other Liberal-Conservative Civil Wars in the Americas such as the Argentine Civil Wars, the Chilean Civil War of 1829, the Uruguayan Civil War of 1833, the Mexican Civil War of 1857, the Venezuelan Civil War of 1859, Colombian Civil War of 1860, the Uruguayan Civil War of 1864, the Colombian Civil War of 1876, the Colombian Civil War of 1899, the Paraguayan Liberal Civil War of 1922, the Nicaraguan Civil War of 1926, the Paraguayan Civil War of 1947, the Colombian Civil War of 1948, or the Costa Rican Civil War of 1948, nor the various Leftist-Rightist Civil Wars such as the Colombian Civil War, the Salvadoran Civil War, and the Guatemalan Civil War - though the American Liberal-Conservative Civil War included elements from all sides of the political spectrum, the Liberal and Conservative forces were the main factions of importance), the Greater American Republic was formed between Canada and the Provisional American Republic.
The capital of the Republic is Duluth. The Republic is considered the legal successor to the United States of America and Canada. The Republic holds no possessions beyond the North American Plate save for a slither of California along the Pacific Plate; Hawaii, Guam, American Samoa, Puerto Rico, Navassa Island, Guantanamo Bay, the Virgin Islands, the Northern Mariana Islands, and smaller holdings all split off before, during, or immediately after the war up to the formation of the Republic.
The flag, to most viewers, is based upon the Canadian Flag more than upon the former flag of the United States of America, composed of a vertical triband of two red bands along the hoist and fly with a white band in the middle hosting a single blue star. The red symbolizes the blood of all who fought, bled, died for, and would do all of those things in the pursuit of, at the least, some form of people's government, defined as any government where the common person has a vote and say, stretching from the constitutional monarchy to direct democracy. The white stands for the new hope in the Republic. The blue star stands for the Republic itself: united as one, regardless of prior division, loyalty or fealty, a greater whole from the sum of its parts. The ratio of the flag is 2:3.
Playing around with Kitra and GIMP, and seeing weightroom711's 'California if the United States was destroyed by a nuclear war' flag, I remembered how rule-breaking the current flag of California is.
So, adding some little things to my current worldbuilding, I, casually breaking up the USA as one does, splattered the ol' self-altered NPS pictograph ontop of a red bar with a red star on a white field for the 'People's Democratic Repubic of California'.
Could work as a simple redesign of the current flag by itself, or a second head could be added to add onto the NCR flag.
After the War on Terror, the Arab Spring, the Arab Winter, the Saudi-Iranian conflict, and then the MENACASEA collapse, by the mid 21st century, Egypt arose as one of the premier powers of the Ummah. With Hejaz curating Mekkah and Medinah, Al-Qāhirah, Jizah, and Al-Iskandariyyah could focus on more secular, democratic, and scientific endeavours. The crises of the last century as well had forged - or unearthed - an 'Egyptian' identity, attached yet distinct, from the Arabian or Berber identity.
With Egyptian forces maintaining peace in the ruins of the Maghreb and Sudan, with the new clippers and solar ships passing through the Suez, and with a quickly post-industrial population, Egypt - now colloquially known as Kemet - focused national energy into a space program, and became one of the first ten nations during the first century of the space age to develop their own rockets, launch their own astronauts, land on the Moon and Mars, and establish extraterrestrial bases.
While the Pharaoh hasn't returned, nor the Ankh, Egypt, ancient and grandiose, had made it to the stars. Their flag at this time was a 2:3 tricolor triband of Red, White, and Black defaced with a white globe, green ring and moon and cresent. This represent, as officially set by the 2060s, Lower and Upper Egypt, the suffering weathered, and then the foward looking outreach of Egypt among the spatial field, respectively.
The Anarcho-Technological Union of Shackleton is a anarchist polity residing in and around Shackleton crater on the Moon's south pole.
Their flag is composed of a stereotypical 'anarchist' flag with the hoist-bisection in 'technological and lunar' grey, a black roundel hoisting a 'A' whose legs end in circuit-board (and thus technological) symbology surrounded by a grey circle, which represents Shackleton-on-the-pole, and indeed, many have noted that the whole flag looks like a stylized view of their settlement, with the near side in grey and the far side in black.
All but an engorged scientific and cultural experiment, the Anarchism there is all but 'classical' communist/socialist/anarchist. Where the details fall is left to observer and participant alike, but it's still very democratic, very 'free', and communal, though tempered by the harsh realities of living in space. Social control and development does exist along some secret manifesto, but the purges haven't started, not yet at least.
Whether or not in the end the anarchist experiment will 'succeed' without implosion is left to heavy debate. It's only been fifty odd years, after all. Some decry external influence, others seek to spread their way, and others still wish to maintain a community of scientists and technology, free from the pressing demands of profit and capitalism.
Here's another polity from my hard-mundane scifi setting. Gods, I hope metallic hydrogen was actually reproduced in a lab....
Mangalan Shambhala, or, in English, the 'Martian Place of Peace', is a theocratic Buddhist state formed around Newton Crater (now hosting a large lake, companion lakes, and gentle grassland below the rim) on, well, Mars.
The flag of Mangalan Shambhala is composed of a orange fesswise pall fimbriated white (a horizontal Y with white borders), representing the Three Jewels of Buddhism.
On top of the pall is a white roundel hoisting four rounded orange semi-circles, which represent the Four Noble Truths, and centered in the circle is a stylized Dharmachakra representing the Noble Eightfold Path. The spokes of the Dharmachakra are a fluffy star, representing spatial and expansive matters/aspirations.
As per their national reckoning of Buddhism, it is ruled by the Maitreya, or the future perfect Buddha; at least, this is the title for their leader, who functions as an absolute theocrat, who is focused on fulfilling the prophetic Kalacakra tantra and to defeat the myriad of 'dark forces' tormenting humanity, with a schedule slated for 2424 AD/467 SE.
To fulfill this goal, extensive mining operations, arms production, militarization, and propaganda is churned out of Mangalan Shambhala at astonishing and inhumane rates. It is rated as a rogue state with abysmal human rights and democracy thereof by the rest of the inhabited solar system, but unlike other such polities (which normally consists of rich fundamentalists, their inner circle, their followers and a cheap off-the-market inflatable habitat or two floating in space or on some rock) their expansive holdings and technology gives them a potentially painful bite behind their bark.
Colors: 3: Dark Grey, orange, and white, which symbolize the darkness of existence, concurrent affairs, and space; Buddhism; purity, and holiness, respectively.
Here it is in flagwaver.