Operation Overcast
At the end of WW II, as well as after WWII. both the US and the Soviet Union were keen to get their hands on German scientists, as in many fields, the Germans had proven to have superior scientific knowledge. The Germans, e.g., were the only ones to possess supersonic rockets, nerve gas, jet aircraft, guided missiles, stealth technology and hardened armour.
After the war, project Paperclip - also known as Operation Paperclip - came into existence. Its goal was to transfer German scientists to the States where they would be offered immunity from prosecution on the condition that they handed over the results of their research and agreed to continue their work, yet this time for the US Government. Werner Von Braun, e.g., was one of those scientists.
Most of them ended up in Los Alamos and Whitesands (New Mexico), and in San Antonio (Texas).
There are reliable indications that the Germans also possessed anti-gravity devices, and that that technology was transfered to Whitesands. There also are persistent rumours that this technology was based on extraterrestrial technology.
From Wikipedia:
Operation Paperclip was a secret United States intelligence program in which more than 1,600 German scientists, engineers, and technicians were taken from former Nazi Germany to the US for government employment after the end of World War II in Europe, between 1945 and 1959; several were confirmed to be former members of the Nazi Party, including the SS or the SA.
The effort began in earnest in 1945, as the Allies advanced into Germany and discovered a wealth of scientific talent and advanced research that had contributed to Germany's wartime technological advancements. The US Joint Chiefs of Staff officially established Operation Overcast (operations "Overcast" and "Paperclip" were related, and the terms are often used interchangeably) on July 20, 1945, with the dual aims of leveraging German expertise for the ongoing war effort against Japan and to bolster US postwar military research. The operation, conducted by the Joint Intelligence Objectives Agency (JIOA), was largely actioned by special agents of the US Army's Counterintelligence Corps (CIC). Many selected scientists were involved in the Nazi rocket program, aviation, or chemical/biological warfare. The Soviet Union in the following year conducted a similar program, called Operation Osoaviakhim, that emphasized many of the same fields of research.
The operation, characterized by the recruitment of German specialists and their families, relocated more than 1600 experts to the US. It has been valued at US$10 billion in patents and industrial processes. Recruits included such notable figures as Wernher von Braun, a leading rocket-technology scientist. Those recruited were instrumental in the development of the US space program and military technology during the Cold War. Despite its contributions to American scientific advances, Operation Paperclip has been controversial because of the Nazi affiliations of many recruits, and the ethics of assimilating individuals associated with war crimes into American society.
The operation was not solely focused on rocketry; efforts were directed toward synthetic fuels, medicine, and other fields of research. Notable advances in aeronautics fostered rocket and space-flight technologies pivotal in the Space Race. The operation played a crucial role in the establishment of NASA and the success of the Apollo missions to the Moon.
Operation Paperclip was part of a broader strategy by the US to harness German scientific talent in the face of emerging Cold War tensions, and ensuring this expertise did not fall into the hands of the Soviet Union or other nations. The operation's legacy has remained controversial in subsequent decades.