URE Core Systems: 64 worlds
Sol system
*Republic of Earth and Luna (confederal, parliamentary republic; POP: 10,675,329,205 billion citizens)
**Luna Confederate States (confederal, presidential democracy; POP: 2,987,107 million citizens)
*Federal Republics of Mars (supranational, presidential republic; POP: 9,192,658,455 billion citizens)
*Jovian Commonwealth (parliamentary republic; POP: 56,233,181 million citizens)
*Republic of Titan City (constitutional republic; POP: 3,864,988 million citizens)
Alpha Centauri system
*Republic of Vekta (parliamentary republic; POP: 1,877,612,569 billion citizens)
*Republic of New Louisiana (presidential republic; POP: 56,717,988 million citizens)
*Republic of Thebes (federal democracy; POP: 608,274,933 million citizens)
*Commonwealth of Haven (parliamentary confederation; 814,336,957 million citizens)
Gamma Centauri system
*Federal Commonwealth of New Harmony (federal, parliamentary republic; POP: 67,346,512 million citizens)
Tesla system
*Federation of Herschel (federal republic; POP: 21,654,934 million citizens)
Arcturus system
*United States of New America (federal, presidential republic; POP: 323,981,311 million citizens)
*Republic of Sargasso (representative, parliamentary republic; POP: 104,227,812 million citizens)
Beta Khan 19 system
*Republic of Cascade (parliamentary republic; POP: 543,221,098 million citizens)
*Republic of Lenapi (constitutional republic; POP: 176,865,287 million citizens)
Alpha Serpentis system
*Federal Commonwealth of Ruthersburg (federal, presidential republic; POP: 69,344,122 million citizens)
*Republic of Lodestone (representative, constitutional republic; POP: 2,432,126 million citizens)
*Dominion of Lostwithiel (representative democracy and constitutional monarchy; POP: 13,846,211 million citizens)
Serpenti 81 system
*Republic of Forseti (representative, constitutional republic; POP: 558,422,743 million citizens)
Omega Serpentis system
*Republic of Phemios (representative democracy; POP: 712,368,041 million citizens)
*United Republic of Ithaka (federal, presidential, parliamentary republic; POP: 11,543,093 million citizens)
*Commonwealth of Terradas (parliamentary, presidential republic; POP: 34,882,137 million citizens)
Eridani 73 system
*Commonwealth of Foundation (parliamentary democracy; POP: 78,355,106 million citizens)
Kepler 22 system
*Commonwealth of New Honshu (parliamentary republic; POP: 2,633,865,109 billion citizens) [1 planetary (major) colony/3 planetary (minor) colonies/16 lunar colonies/82 colony platforms]
Serpent 68 system
*Oplotom Commonwealth (federal, semi-presidential republic; POP: 1,543,782,069 billion citizens)
Roswell 163 system
*Republic of Podere (parliamentary, presidential republic; POP: 633,451,287 million citizens)
Kepler 57 system
*Commonwealth of Hardscrabble (parliamentary confederation; POP: 412,739,850 million citizens)
Gliese 667 system
*Federated Republic of Chosun (federal, presidential, parliamentary republic; POP: 308,649,106 million citizens)
AN: These are first worlds to be colonized by humanity, AU, I'll update the author's note later.