Humanity advanced early in its history. Its technology became highly sophisticated, and it outward expanded along the Orion Arm to escape Forerunner control thousands of years before the activation of the Halo Array. Humanity once formed an alliance with the San'Shyuum and later warred against the nascent Flood. Humanity drove the Flood from the galaxy for the next several millennia, but the conflict caused a war with the Forerunners. The Forerunners won and, as punishment by the Didact (Forerunner leader) reduced humanity to a pre-technological state: he stripped them of their technology, smashed their civilizations, and exiled their remnants to Earth. Though The Librarian watched over and guarded humanity as the race scraped itself back together, The Didact used the Composer to destroy a small portion of mankind. Because of this The Librarian locked The Didact away for the safety of humanity and himself.
The development of human civilization as modern humans know it began ten thousand years ago with the Neolithic Revolution, during which humans learned how to systematically use plants to produce edible food-energy. The stability thereby gained enabled more permanent settlements and the development of ever more complex tools.
Innovative toolmaking and the domestication of other species provided human populations greater and greater power to expand their populations, and trade ensured the diffusion of new technologies to adjacent groups. These exploding populations formed the first genuine civilizations over 8,500 years ago in Northern Africa, Southwest Asia, Asia Minor, and elsewhere soon after. The infrastructure of civilizations continued to grow in size and complexity as innovative technologies and larger populations increased food-energy availability. Economic, political, and scientific advancement continued to quicken by automating many tasks in the Industrial Revolution. Human civilization rapidly developed during the 18th through 20th centuries, which comprised an era known as the "Industrial Revolution." The major political and economic ramifications of the rise constitutional governments and refined capitalist resource management techniques enabled such important inventions as automobiles, electrical appliances, and aircraft to enter use at unprecedented scales. Humanity's understanding of medicine and chemistry raced ahead and created anesthesia, along with plastics that could cheaply fulfill an enormous amount of material roles (with the better preservation of food being one of its greatest functions). The average human lifespan of approximately forty-five years leapt to eighty or one hundred years because of antibiotics and other medicines combined with better food production and preservation: the age-old scourges of plague and famine were nearly eradicated.
Mankind more efficiently applied previous sciences and arts, and the art of the military would prove no exception to this pattern. Armed conflicts rapidly changed from the primitive, melee-oriented wars of the past: after two massive wars within the first 50 years of the 20th century, humans invented superior firearms, automatic weapons, radar, tanks, missiles, jet engines, and ultimately the atomic bomb, which became the most powerful weapon then known and later a key component of human arsenals during the brutal war against the Covenant.
Over the next 60 years the superpower nations of the United States of America and the Union of Soviet Socialist Republics (succeeded by the Commonwealth of Independent States) competed in a period of military and cultural tension known as the "Cold War." The lethality of humanity's relatively new warfare technologies, tactics, and battlefield doctrines became more destructive and precise as each nation tried to intimidate the other. In the 1950s, the Soviet Union launched the earliest satellite and sent the first human, Yuri Gagarin, into space, officially making humans space faring (and thus at Tier 5 in the Technological Achievement Tiers). The United States successfully placed the first human, Neil Armstrong, on the Moon, and eventually surpassed the Soviet Union's space faring and military production capabilities; their doctrines would heavily influence the UNSC in later centuries.
These advancements caused the Digital Revolution, in which computing machines enabled scientific discovery and technological development to accelerate with explosive speed. As larger urban centers and tools for civilian and military uses, along with more modern economic and political systems, developed, individuals enjoyed longer, more pro-creative, and more comfortable lives, now virtually impervious to the creatures from whose midst they sprang. Thus-unchecked, the human population eventually exceeded the carrying capacity of earth by several billion and ultimately created a great need for humans to expand off world.
Additionally, the creation of the Internet in the late 20th century revolutionized communication and data processing, thereby further accelerating mankind's rate of technological progress. World politics also changed with the formation of the United Nations. The religiously neutral nature of many of these constitutional style governments, along with scientific and logical explanations for phenomena and methodology, relatively diminished the weight of ideological dogma. Religion would remain a staple of human societies insofar as advocating personal ethical codes, though unlike that of the Covenant, it was no longer primarily a mere framework to justify a large, hierarchical system of differing castes and birthrights. In the late 20th century, satellites used solar energy instead of primitive battery sources and could therefore work long enough to send and retrieve data and communications and be a method of civilian and military navigation. Although much of the technology used during this time is disregarded as "primitive" by the standards of the 26th century, they were all somehow a precursor to all of technologies utilized later by the UNSC.
The species was able to explore the space immediately surrounding their home planet in the 20th century, as the population began to advance beyond the capacity of the planet to comfortably sustain their civilization. The subsequent conflict over resources, economics, religion and politics on Earth gave way to numerous wars. Furthermore, these tensions put great pressure on the species in the beginning of the twenty-third century, and the transnational organization that became the Unified Earth Government (UEG) engaged in more frequent space colonization and sought to represent the entire species, even though no one state ever previously ruled the entire human race. The development of Slipspace travel in 2291 helped the UEG engage in spreading the human race beyond their home solar system, relieving the serious ecological pressure on the home world.
Simultaneously, this expansion was also to usher in promising new opportunities for humanity, as some of these colonies, such as planet Reach with its bountiful titanium deposits, could offer abundant stores of raw materials that had otherwise been considerably unique and scarce on Earth. With the initial advent of interplanetary trade driving down the costs of what had once been an expensive implementation of their technology - such as the forging of space-worthy ships and naval vessels - the effects from these carefully implemented first colonization projects helped to ensure that interstellar trade, travel and communication were to be more commonplace amongst the general populace in the ensuring centuries, eventually granting humanity the capacity to expand to hundreds of worlds and establish colonies at enhanced rates.
The Great War
The species as a whole was finally pushed into major conflict when, after several centuries of spreading throughout many star systems and inhabiting hundreds of worlds, they discovered the violent, genocidal, theocratic Covenant. As the decades-long war wore on, the human race gained the controversial reputation as a worthy adversary against the Covenant, despite the fact that they were technologically, numerically and physically inferior. Humans with the help of the SPARTANs, could hold out in ground combat and sometimes defeated the Covenant (on the rare occasion, without the aid of the SPARTANs), but in space the Covenant had virtually undisputed supremacy, thanks to their talents for re-purposing Forerunner technology, space tactics and not to mention whenever they were defeated on the ground, they would glass the planet.
Humans have been able to show great bravery when facing insurmountable odds. Some of the members of the Covenant wonder why the Hierarchs had refused to allow the humans to join them, as they had with the crucial contributions of the SPARTAN-IIs been able to hold steadfast even when outmatched in almost every way. However, despite great courage, the future seemed dark for the survival of the human race as the Covenant continued to wipe out their colonies, marching ever closer to Earth. On October 20, 2552, Earth was found. In the ensuing battles over possession of Earth, humanity suffered heavy casualties.
March 3, 2553, saw the end of the Human-Covenant war as a Pyrrhic victory for humanity and their new found Sangheili allies - the majority of the Covenant Loyalist military having been defeated at Delta Halo by the Sangheilian Fleet, and the rest annihilated by the joint Elite-UNSC forces at the Ark. This victory came in time to save the human homeworld, thanks to the actions of the Arbiter and SPARTAN John-117.
Humans are warm-blooded mammals who give birth to live offspring, and nourish their offspring with milk. They have five fingers, one being an opposable thumb, which a few Covenant species do not have. It was a major part in helping humans dominate on Earth. Their circulatory system is closed and consists of one heart and a network of blood vessels and red blood due to the iron-based hemoglobin of humans, as well as two lungs which breathe mainly a nitrogen-oxygen-based atmosphere. Externally, they have more hair than most Covenant species. Their eyes have more pinpointed pupils allowing for good vision, and their sense of hearing can detect very low pitch sounds. However, their sense of smell is fairly poor. They are omnivorous, meaning that they will eat both meats and plants, as well as consume high calcium foods, such as the milk of other animals, in great quantities. They have a more developed bone structure for protecting organs.
Humans are lean and possess relatively little muscle tissue. The relatively low power output of the human anatomy translates into a low upkeep for their sustained bodily functions. With a metabolism well-suited for the moderation of internal body temperature, less recovery time is required from physical exertion compared to other species. Though potential prey would easily out pace them at first, by pure stamina alone, early humans were able to wear down their quadruped game as it succumbed to heat stroke far sooner than they would.
In the 22nd century, Earth was deemed overpopulated, jump-starting the colonization programs of the time. The population of known human settlements preceding the Human-Covenant war would amount to 39 billion humans according to the UNSC and Halsey's records and estimates. After twenty seven years of war with the genocidal Covenant, Cortana approximated the death count to 23 billion (16 billion remaining).
Halo is a military science fiction first-person shooter video game franchise managed and developed by 343 Industries, a subsidiary of Xbox Game Studios. Halo was originally developed by Bungie Studios. The series centers on an interstellar war between humanity and an alliance of aliens known as the Covenant.
The games in the series are critically acclaimed, with the original considered the Xbox's "killer app".