The first planet in the Delta Sokirin system was detected in 19121 and was a gas giant later designated Delta Sokirin VI (Tahe). It was detected by astronomical observation of small variations in the Doppler shift of light from Delta Sokirin. Delta Sokirin VI had an orbital period of 5124 standard days, and an estimated mass of 0.1032% that of Delta Sokirin.
The Delta Sokirin system is 45 standard light years from the homestar away from the galactic core. It was a candidate system during the Second Expansion, but was removed from consideration early in the planning phases due to the distance to the system.
Delta Sokirin was also a candidate during the Third Expansion, and this time a probe was sent to the system. This probe found 11 planets, 3 rocky planetoids, 2 minor planets, 5 gas giants and one (Delta Sokirin IV) suitable for colonisation. Delta Sokirin was once again rejected for colonisation due to the discovery of several suitable systems close together that lay in the direction of the galactic core. It was decided to colonise these planets, as it was hoped that the proximity would improve trade between the fledgling colonies.
By the time of the fourth expansion, improvements in FTL travel and communication made the distance between Delta Sokirin and the Extended Kingdom less of a burden than it had been during previous expansions. Together with the discovery of several suitable systems between Delta Sokirin and the homestar, this made Delta Sokirin more suitable for colonisation as part of the Fourth Expansion.
The lead ship left the homeworld on 20929-004, tasked with setting up orbital facilities in orbit around Delta Sokirin IV and VI and performing the initial survey of Delta Sokirin IV. The main colony fleet left the home year just over a year later on 20930-42.
The colony fleet was led by Captain Stephen Yrf, who had previously been a military officer and then mayor of Shiran, the 6th largest city on the homeworld. Landfall was on 20931-211, and on this day the colony on Delta Sokirin was officially named New Shiran.
Taken from A Brief History of New Shiran and it's Role in the Extended Kingdom