Tau'ri-Genii conflict

Tau'ri-Genii conflict was a rivalry between two powers in Pegasus galaxy. It mostly ended after Ladon Radim successfully took power.

First contact
First contact between two races occurred during first year of Atlantis expedition operations. Genii had trade relationship with Athosians but pretended to be simple farmers. After establishing alliance between expedition and Athosians, Teyla Emmagan introduced Genii to the expedition is order to trade for food supplies. After Rodney McKay and John Sheppard stumbled into Genii underground base, they discovered their true level of technology and proposed the alliance.

First joint operation against Wraith didn't end well. After their return Cowen tried to force Tau'ri to surrender their gateship to them, but didn't succeed.

Attempt of capturing Atlantis
Using the opportunity when city was almost abandoned due to the Lantean storm, commander Acastus Kolya lead the group in attempt to raid Atlantis for supplies they needed. He eventually was forced to retreat, declaring John Sheppard his personal enemy.