Project Silver
At once, across the galaxy, all the 741 sapient races were greeted by a powerful, nigh-godly species. When they arrived, they taught the people that they had came to them before in different forms. Some sapients had only just discovered electricity, and were taught aerospace engineering in order to be able to keep up with the rest, and all were given technology to access the rifts, cracks in the galaxy that with the proper method, can allow one to travel lightyears in mere hours allowing all the galaxy the freedom of the stars.
Soon after, the 'Angels' left the galaxy to their own devices. Some used their new freedom to conquer, while others sought new resources. One faction claimed to have the authority of the Angels to control the galaxy in their name. Many other factions have risen and fallen since that fateful day.