The Kerbals accelerated their technology much quicker than any other species due to the large amount of Forerunner Artifacts located in the planet's Arctic region. According to Human research the Kerbals reached Technological Tier 4 in the year of 1935, in 2134 Technological Tier 3 was reached, Technological Tier 2 was achieved in 2263, and Technological Tier 1 was finally reached in 2381. During the time in between the the encounter by Unngoy and the reaching of Tier 1 they attempted to surpass Tier 1 but it is essentially impossible. The first contact with any species of non-Kerbals was in 2613 when an Unngoy Frigate had a slipspace malfunction and ended up in the atmosphere of Kerbin and it did not end well. When the ship arrived it had engine failure and ended up crashing in to a Forer