Rockets have existed for ages. They were used primarily for military purposes as artillery, and were simple, light it off and watch it fly types of rockets. When you ask "we", I choose to take it as humanity as a whole. There's a Chinese myth of Wan Hu, who strapped rockets to his chair and supposedly went to space. While this did not happen, it showed that this was an idea that man has held for awhile. The first actual attempts to put scientific to space flight was Russian schoolteacher Konstantin Tsiolkovsky in the late 19th century, where he proposed designs, experimented with wind tunnels, and made formulas, which are used today. The next serious attempt was Robert Goddard's liquid fuel rockets, which was a first away from older solid propellents. While he had small amounts of government support, reaching space was not really on Goddard's design board. The first major and true applications of modern Spaceflight came from the Verein für Raumschiffahrt (VfR) or Society for Space Travel, and Gruppa izucheniya reaktivnogo dvizheniya (GIRD) or Group for the Study of Reactive Motion. The VfR launched small rockets funded by patrons and viewing parties, and were finally picked up by the German Army in 1932, a year before Hitler came to power, to seek a way around the Treaty of Versailles to develop new weapons. von Braun saw this as a way to milk the German Army for funds for his own space ambitions. He wished for Spaceflight, which he sought to help achieve through his Aggregate rockets. The Aggregate-4, or the Vergeltungswaffen-2 (V2 as named by Propaganda Minister Goebbels) was the product of von Braun and his team's work on rocket research, and became the first vehicle to enter space. In the Soviet Union, a similar programme was undertaken, but many of its best scientists were purged by Stalin during the terror, setting back research massively. After the end of the war, the A-4 rocket and it's team formed the base of the American Redstone rocket, itself a precursor to many United States launch vehicles. The A-4 rocket and several low-level engineers were captured by the Soviet Union, with Sergei Korolev taking head of a new programme, along with others such as Valentin Glushko, to deconstruct and remake the rocket. The A-4 became the R-1 and was extended to the R-2. Here, without von Braun, a Russian twist takes hold, where Korolev and his team design the R-7, the first ICBM and space vehicle, which lives on today in the form of the Soyuz rocket. Without the A-4 and von Braun, the two space programs we know of today would have been vastly different, and it has played a crucial roll in both of their developments. Sources: von Braun: Dreamer of Space; Engineer of War / Korolev: How One Man Masterminded the Soviet Drive to Beat America to the Moon / Red Moon Rising: Sputnik and the Hidden Rivalry that Ignited the Space Age